Consanguinidad no declarada en pacientes peruanos con trastorno del neurodesarrollo detectada a través de micromatrices

Introducción. La consanguinidad es la unión entre personas que comparten un ancestro en común, y cuya descendencia presenta un mayor riesgo de aparición de enfermedades autosómicas recesivas, manifestándose en algunos pacientes como trastornos del neurodesarrollo. Objetivos. Describir la consanguinidad parental no declarada en pacientes menores de 18 años con trastornos del neurodesarrollo, descubierta mediante el análisis cromosómico por micromatrices. Métodos. Se realizó el análisis cromosómico por micromatrices a 967 pacientes con trastorno del neurodesarrollo entre 2016 y 2021. Fueron seleccionados los pacientes con regiones de homocigosidad (ROH) con un valor superior a 0,5%. Resultados. Se evaluó a 288 pacientes, el 58,3% fueron varones y el 29,8% presentó una ROH mayor o igual a 0,5%. Se encontró que el 25,9% y el 0,83% de los pacientes tenían padres con un quinto y primer grado de consanguinidad no declarada, respectivamente. Los departamentos con mayor frecuencia relativa de consanguinidad no declarada por cada 10 000 habitantes fueron Huancavelica, Cajamarca y Apurímac. Conclusión. En Perú, existen regiones donde se evidencia uniones parentales consanguíneas, el cual es un factor de riesgo alto para la aparición de enfermedades recesivas autosómicas en su descendencia, como los trastornos del neurodesarrollo.

Introduction. Consanguinity is the union between people who share a common ancestor, and whose offspring have a higher risk of autosomal recessive diseases, manifesting in some patients as neurodevelopmental disorders. Objectives. To describe non-declared parental consanguinity of patients under 18 years of age with neurodevelopmental disorders, discovered by chromosomal microarray analysis. Methods. Chromosomal microarray analysis was performed on 967 patients with neurodevelopmental disorders between the years 2016-2021 and were selected to patients with regions of homozygosity (ROH) with a value greater than 0.5%. Results. 288 patients were evaluated, 58.3% of the patients were male and 29,8% presented an ROH greater than or equal to 0.5%. We found 25.9% and 0.83% of the patients had their parents of a fifth and first degree of consanguinity not previously declared, respectively. The most frequent neurodevelopmental disorder was delayed psychomotor development with 38.2%. The departments with the highest frequency relative of non declared consanguinity were Huancavelica, Cajamarca y Apurimac. Conclusions. In Peru, non-declared parental consanguinity is frequent, which is a high-risk factor for the appearance of autosomal recessive diseases in their offspring, how neurodevelopment disorders.

DNA rare copy number alterations in Reinke's Edema

Abstract Introduction: Reinke's Edema (RE) is a laryngeal lesion related to excessive tobacco smoking, voice overuse, and laryngopharyngeal reflux. Although the risk of malignancy has been considered low in literature, RE is classified among precancerous lesions. Objectives: We investigated DNA Copy Number Alterations (CNAs) in specimens of RE and its potential association with malignant progression. Methods: We used array-based comparative genomic hybridization (aCGH, Agilent 4 × 180 K platform) to study eight RE cases. All patients were heavy tobacco users for at least 30 years, and none of them progressed to cancer in the follow-up (>8 years). Two RE presented mild dysplasia, one moderate dysplasia, and no histological alterations were found in the remaining five cases. CNAs were compared with the Database of Genomic Variants (DGV) and genes mapped on altered regions had their functions annotated. Results: Six of eight patients showed different rare copy number alterations on chromosomes 2q37.3, 4q13.1, 4q13.3, 7q11.22, 10p14, and 13q34. A gain of the whole chromosome 8 were detected in one case. Of interest, four of eight RE cases showed copy number imbalances involving genes previously described in several tumor types (RASA3, COL6A3, LINC00707, LINP1, SMR3A, and SMR3B). Conclusion: The genomic imbalances herein found in RE have the potential to contribute to the phenotype but with limited or no risk of cancer. A long-term follow-up in a large series of patients could clarify the mechanisms involved in the malignant progression of RE. Level of evidence: 4.

Analysis of whole genome expression profile for the effect of melatonin on radiation-induced intestinal injury in mice / 中华放射医学与防护杂志

Objective:To elucidate the change of whole genome expression profile for the effect of melatonin on radiation-induced intestinal injury in mice.Methods:C57BL/6J male mice were administrated with melatonin at 10 mg/kg body weight by intraperitoneal injection once a day for five consecutive days before abdominal irradiation with 14 Gy of γ-rays. Small intestines were harvested 3 d after radiation. GO annotation and KEGG pathway of the differential genes involved in small intestine were explored by DNA microarray analysis.Results:Compared with the control group, 584 differential genes were up-regulated and 538 differential genes were down-regulated for administration group pre-irradiation. The overlapping differential genes were selected from the irradiated mice and the administrated mice pre-irradiation. There were 324 up-regulated genes and 246 down-regulated genes unique to the administrated mice pre-irradiation. GO annotation analysis of the differential genes indicated that the top 15 significantly enriched biological processes for the administrated mice pre-irradiation mainly included autophagosome assembly (GO: 0000045), autophagosome organization (GO: 1905037) and regulation of acute inflammatory response (GO: 0002673). The genes ATG12, ATG16L2 and AMBRA1 were involved in autophagosome assembly and autophagosome organization. The genes C3, CPN1, CD55, CFP, CNR1, C1QA, C2 and CREB3L3 were involved in the regulation of acute inflammation response. KEGG pathway analysis of the differential genes involved indicated that the top 15 significantly enriched pathways for the administrated mice pre-irradiation mainly included O-glycan biosynthesis (hsa00512), glycosphingolipid biosynthesis (hsa00603), ECM-receptor interaction (hsa04512) and biosynthesis of unsaturated fatty acids (hsa01040). qRT-PCR verification showed that the expressions of ATG12 and ATG16L2 genes involved in autophagy for the administrated mice pre-irradiation increased significantly compared with the irradiated mice ( t=2.40, 4.35, P<0.05). Conclusions:The differential genes related with the biological process of autophagy, acute inflammatory response and the pathway of unsaturated fatty acid biosynthesis might be involved in the effect of melatonin on radiation-induced intestinal injury.

Genetic diagnosis of microcephaly / 中华妇产科杂志

Objective:To explore the diagnostic value of chromosome karyotype analysis, chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in microcephaly.Methods:A total of 9 cases of microcephaly fetuses diagnosed by prenatal ultrasound or children with microcephaly diagnosed after birth were selected from the Sixth Affiliated Hospital of Guangzhou Medical University from January 2014 to August 2022.Karyotype analysis and/or CMA were used to detect. The cases with negative karyotype analysis and CMA results were further sequenced by trio-based WES (Trio-WES). Then the coding genes contained in the pathogenic copy number variation (CNV) fragments were analyzed by gene ontology (GO) enrichment. The genes related to the development of the central nervous system contained in the pathogenic CNV and the pathogenic genes found by Trio-WES were combined for gene interaction network analysis.Results:In this study, 9 cases of microcephaly were recruited, with the time of diagnosis ranged from 23 weeks of gestation to 7 years after birth, and the head circumference of fetus or children ranged from 18.3 to 42.5 cm (-7SD to -2SD). Karyotype analysis was detected in all 9 cases and no abnormality result was found. Eight cases were detected by CMA, and one abnormal was found. Five cases were detected by Trio-WES, and two cases were detected with likely pathogenic genes. The GO enrichment analysis of the coding gene in the 4p16.3 microdeletion (pathogenic CNV) region showed that: in biological process, it was mainly concentrated in phototransduction, visible light; in terms of molecular function, it was mainly concentrated in fibroblast growth factor binding; in terms of cell components, it was mainly concentrated in rough endoplasmic reticulum. Gene interaction network analysis suggested that CDC42 gene could interact with CTBP1, HTT and ASPM gene.Conclusions:CMA could be used as a first-line detection technique for microcephaly. When the results of chromosome karyotype analysis and/or CMA are negative, Trio-WES could improve the detection rate of pathogenicity of microcephaly.

Prenatal diagnosis and pregnancy outcome of fetuses with isolated echogenic bowel / 中华围产医学杂志

Objective:To investigate the clinical value of isolated fetal echogenic bowel (FEB) as an indicator for invasive prenatal diagnosis.Methods:This retrospective study enrolled 183 pregnant women who were diagnosed with isolated FEB and underwent invasive prenatal diagnosis in Fujian Maternity and Child Health Hospital from August 2013 to January 2021. Clinical data including the results of conventional karyotyping and chromosomal microarray analysis (CMA), cytomegalovirus (CMV) DNA loads in amniotic fluid and pregnancy outcomes were reviewed analyzed. Chi-square test was used for statistical analysis Results:Karyotyping was performed on all of the 183 fetuses and three (1.64%) aneuploidies (one case of trisomy 21, one trisomy 18 and one 47,XYY syndrome) were detected. One trisomy 21 and four pathogenic (P)/likely pathogenic (LP) copy number variation (CNV) were detected among 108 fetuses who received CMA. The detection rate of P/LP chromosomal abnormalities by CMA was higher than that by karyotyping, but there was no significant difference between them [4.63% (5/108) vs 0.93% (1/108), χ 2=1.54, P>0.05]. In addition, three cases of variants of uncertain significance (VOUS) were detected by CMA. CMV DNA loads of fetal cells in the amniotic fluid samples of the 166 cases were determined, and only one (0.6%) was positive (CMV DNA up to 7.01×10 6 copies/ml), and no abnormalities were found in karyotype analysis and CMA detection. A total of 176 cases were followed up, and among them only one case of intrauterine infection and seven cases (three aneuploidies and four P/LP CNV) of chromosomal abnormalities were terminated after genetic counseling. Three fetuses with VOUS and other 165 fetuses without chromosomal abnormalities had a good prognosis after birth. Conclusions:Isolated FEB may be the abnormal ultrasound finding in fetuses with chromosomal abnormalities or CMV infection. Prenatal genetic testing and the exclusion of intrauterine infection are important for management during pregnancy and prognosis assessment of FEB.

Clinical value of different genetic testing methods for detection of true fetal chromosome mosaicism / 中华围产医学杂志

Objective:To investigate the performance of chromosome karyotype, chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH) in prenatal diagnosis of true fetal chromosome mosaicism. Methods:This retrospective study enrolled 40 women with true fetal chromosome mosaicism from 4 071 singleton pregnant women who were indicated for and underwent amniocentesis or/and cordocentesis in the the First Affiliated Hospital of Sun Yat-sen University from April 2018 to August 2021. The results of chromosome karyotyping, CMA and FISH, the types of chromosomal mosaicism, mosaicism ratio and pregnancy outcomes were analyzed using Chi-square test. Results:(1) The detection rate of true fetal mosaicism was 0.98% (40/4 071). (2) Sex chromosome mosaicism accounted for 42.5% (17/40). Other chromosomal mosaicism involved chromosomes 21, 22, 18, 16, 7, 12, 15, 17 and 20, as well as balanced chromosomal translocation. (3) The detection rate of true fetal mosaicism by chromosome karyotyping was 77.4% (24/31) from amniotic fluid samples and 10/19 from umbilical cord blood samples, while that data by CMA was 76.7% (23/30) and 7/11,respectively. (4) Of the 40 pregnant women with fetal chromosome mosaicism, FISH test was performed on 20 cases (14 cases were verified with both amniotic fluid and umbilical cord blood samples, five with amniotic fluid samples and one with umbilical cord blood sample), and all of the diagnosis of mosaicism were confirmed. For those with mosaicism ratio <30%, the detection rate by FISH was higher than that by CMA among amniotic fluid samples [14/19 vs 43.5% (10/23), χ2=3.88, P=0.049]. (5) Among the 40 pregnant women, five were lost to follow-up; 18 chose to terminate the pregnancy; and 17 continued the pregnancy to delivery. No abnormalities in mental or physical development were reported in the 17 neonates after birth or during on-line follow-up between 6 to 24 months old. Of the 14 pregnant women with mosaicism ratio <30% which confirmed by FISH, eight chose to continue the pregnancy, and no abnormalities in mental development or growth were found in the neonates. Conclusions:In prenatal diagnosis of true fetal choromosome mosaicism, the incidence of sex chromosome mosaicism is the highest. FISH may improve the prenatal diagnosis rate of mosaicism and is more accurate in determining the mosaicism ratio. The combination of FISH, CMA and chromosome karyotyping would significantly improve the detection rate of chromosomal mosaicism and assess the mosaicism ratio more accurately, which is of great value in clinical consultation and evaluation of fetal prognosis.

Prenatal phenotypic analysis and genetic counseling for 22q11.21 microdeletion and microduplication syndrome / 中华围产医学杂志

Objective:To analyze the prenatal clinical phenotypes and pregnancy outcomes of fetuses with 22q11.21 microdeletion and microduplication syndrome to provide a basis for clinical genetic counseling.Methods:This retrospective study involved the cases diagnosed with 22q11.21 microdeletion or microduplication by chromosomal microarray analysis (CMA) due to abnormal ultrasound findings, advanced maternal age, or high-risk pregnancies indicated by serum screening in the Prenatal Diagnosis Center of the First Affiliated Hospital of Air Force Medical University from January 2015 to January 2022. Clinical phenotypes and pregnancy outcomes of the fetuses were analyzed and described.Results:Among 9 141 cases referred for CMA during the study period, 77 cases (0.8%) were diagnosed as 22q11.21 microdeletion or microduplication, including 62 (80.5%) with 22q11.21 microdeletion and 15 (19.5%) with microduplication. In the 22q11.21 microdeletion cases, 58 had typical deletion, and four had atypical deletions, but all fetuses carried TBX1 gene that was clearly associated with congenital heart disease. The 15 fetuses with 22q11.21 microduplication including 14 in the typical region and one in the atypical region. Forty-eight (77.4%) out of the 62 fetuses with 22q11.21 microdeletion were complicated by congenital heart defects, including 28 with conotruncal defects. Five of the 15 fetuses with 22q11.21 microduplication were complicated by congenital heart defects. The cases were followed up on telephone at three to six months after the expected date of delivery. Among the 62 cases with 22q11.21 microdeletion, 52 terminated pregnancies, five were lost to follow-up, and five were delivered (one died after one month of premature delivery, one was born with anal advancement and growth retardation, and three were followed up without obvious abnormality). Among the 15 cases with 22q11.21 microduplication, four terminated pregnancies, two were lost to follow-up, and nine gave birth (eight were followed up without obvious abnormality, one grew slowly). Conclusions:The application of CMA in the prenatal diagnosis of 22q11.21 microdeletion and microduplication fetuses, and the comprehensive analysis of clinical manifestations and pregnancy outcome combined with ultrasonic diagnosis are of great significance in guiding the treatment and rehabilitation after birth of an affected child. Genetic counseling for cases with 22q11.21 microdeletion and microduplication syndrome should be cautious and consider ultrasound findings.

Clinical and Genetic Profile of Children With Short Stature Presenting to a Genetic Clinic in Northern India

Objective: To define the spectrum of genetic disorders in patients with short stature visiting the genetic out-patient department in a tertiary care hospital. Methods: A chart review was done for 455 individuals (10 months-16 yrs) with short stature, who were evaluated at the genetic clinic from 1 January, 2017 upto 31 October, 2018. 226 patients who needed detailed evaluation, the spectrum of genetic diagnosis is presented. Results: Proportionate short stature was identified in 63% individuals (n=142) of which 93 (65%) were recognizable syndromes such as Turner syndrome, and William syndrome, and RASopathies. In clinically undefined syndromes (39, 27%), a diagnosis could be made by karyotype (n=3/10), chromosomal microarray (6/12) and exome sequencing (1/6). In the 84 children in the disproportionate short stature group (37%), lysosomal storage disorders (LSDs) (45%, n=38) were identified by enzyme analysis in 86.8% and skeletal dysplasias (44%, n=37) identified by skeletal survey in 89% cases. Conclusions: In undefined syndromic short stature, chromosomal microarray may be the first investigation of choice if phenotyping is not suggestive of a specific genetic syndrome. Exome sequencing can be useful in identifying newer genes among idiopathic and familial short stature cohorts.

Outcomes of Very Preterm Neonates Born by Assisted Reproductive Techniques (ART): A Propensity Score Matched Retrospective Cohort Study

Objective: To compare outcomes of preterm neonates born through assisted reproduction techniques (ART) and non-ART conception. Methods: This retrospective cohort study included very preterm neonates (26 weeks to 31 weeks) admitted to our neonatal unit over a six year period from 2014 to 2019. The primary outcome was composite adverse outcome of mortality or any of the major morbidities i.e., intraventricular hemorrhage (IVH) grade ?3, periventricular leukomalacia (PVL) grade ?2, bronchopulmonary dysplasia (BPD) at 36 weeks, and retinopathy of prematurity (ROP) requiring treatment. Results: Total of 759 neonates (253 in ART group, 506 in non-ART group) were included after propensity score matching for gestational age, sex, and small for gestational age (SGA). Neonates in ART group had similar rates of composite adverse outcome [aOR (95% CI) 0.86 (0.55 – 1.36)], mortality [0.93, (0.53- 1.64)] BPD [1.18, (0.37 – 3.76)]; ROP requiring treatment [ 0.49 (0.14-1.71], and other morbidities. Conclusion: Very preterm neonates born through ART were not at increased risk of adverse neonatal outcomes.

Prenatal diagnosis of Cri-du-chat syndrome: analysis of 11 cases / 中华围产医学杂志

Objective:To investigate the ultrasonographic and genetic features of Cri-du-chat syndrome (CDCS).Methods:In this retrospective study, cases with CDCS diagnosed in Wuxi Maternal and Child Health Care Hospital from 2004 to 2021 and with complete data were reviewed to describe and analyze the maternal serum prenatal screening, non-invasive prenatal testing (NIPT), ultrasound, genetic examination data, and pregnancy outcomes.Results:All cases were diagnosed by karyotype analysis, seven of them were diagnosed prenatally through amniotic fluid, and four were diagnosed after birth through peripheral blood. Five of the seven cases diagnosed prenatally had an abnormal serological screening, including two cases with 5p- indicated by NIPT. Of the 11 cases, prenatal ultrasonography showed cerebellar transverse diameter less than －2 SD in eight cases, including four with cerebellar hypoplasia (CH), two with fetal growth restriction, and two with cranial diameters less than －2 SD. One case was shown with an increased nuchal translucency, accompanying bilateral choroid plexus cysts of the lateral ventricles, and suspected persistent left superior vena cava. No obvious ultrasound abnormality was observed in the remaining two cases. Among the seven cases diagnosed prenatally, excluding one case that refused parental verification, further single nucleotide polymorphism array (SNP array) showed that all six cases inherited the de novo mutations from the parents. The cytogenetic analysis found the breakpoints at 5p13, 5p14, and 5p15 in five, three, and three cases. All seven pregnancies were terminated in the second trimester. Four children diagnosed postnatally presented with CDCS phenotype during the follow-up at three years old. Conclusions:Fetal CDCS should be considered with CH detected by prenatal ultrasonography, though the correlation between CH and CDCS still needs further investigation. Gene mapping with an SNP array is helpful for phenotypic profiling and genetic counseling.

Indications of invasive prenatal diagnosis in third trimester and pregnancy outcome / 中华围产医学杂志

Objective:To analyze the indications for invasive prenatal diagnosis in the third trimester and summarize the pregnant outcome.Methods:Clinical data of 121 women who underwent invasive prenatal diagnosis in the third trimester in the prenatal diagnostic center of the First Medical Center of Chinese PLA General Hospital from January 2016 to December 2020 was retrospectively analyzed. Different genetic diagnostic methods were used according to different indications. Indications and results of prenatal diagnosis, as well as the complications within two weeks after the invasive procedure, pregnancy outcome, and neonatal follow-up of all the participants were described.Results:Among the 121 cases, 107 cases underwent amniocentesis, seven underwent percutaneous umbilical blood sampling, and seven had both procedures performed at the same time (one underwent thoracocentesis at the same time). Newly identified ultrasound abnormalities in the second and third trimesters were the main indications for prenatal diagnosis, accounting for 99.2%(120/121), of which short limbs and fetal growth restriction accounted for 25.0% (30/120) and 20.0% (24/120), respectively. Genetic abnormalities and congenital diseases were detected in 20 cases with a detection rate of 16.5%(20/121). Among them, there were nine cases of achondroplasia, five cases of pathogenic copy number variations, one case of achondroplasia with pathogenic copy number variation, one trisomy 18, one 47,XXX, one tetrasome mosaicism of 12p, one de novo WTX c. 1072(Exon2) C>Tp.R358X heterozygous mutation, and one fetal hypoproteinemia. In addition, six cases with copy number variation of unknown significance (VUS) were detected, noting for a detection rate of 5.0%(6/121). Among the 20 cases with abnormal detection, 15 were terminated, two delivered prematurely before obtaining the prenatal diagnosis results, one underwent cesarean section before obtaining prenatal diagnostic results and two continued the pregnancies. In the six cases with VUS, one was terminated and the other five continued the pregnancy. Only one case had preterm premature rupture of membranes 2 d after amniocentesis and the incidence rate of complications after all kinds of invasive procedures was 0.8% (1/121). During the neonatal follow-up, postnatal whole exome sequencing revealed monogenetic disorder in two cases with normal prenatal diagnostic results; the patient with 12p chimerism had developmental delay; the one with WTX mutation deceased on the day of born; the rest newborns developed normally. Conclusions:As a relatively safe method, invasive prenatal diagnosis in the third trimester is of great importance and value in reducing the miss diagnostic rate of fetuses with severe genetic diseases and birth defects. The appropriate application of prenatal whole exome sequencing could further help to decrease the miss diagnostic rate of monogenetic disorder.

Role of karyotyping combined with chromosomal microarray analysis in prenatal diagnosis of balanced translocation or inversion carriers / 中华围产医学杂志

Objective:To explore the value of karyotyping and chromosomal microarray analysis (CMA) in the prenatal diagnosis of balanced translocation/inversion carriers.Methods:This was a retrospective study involving 117 balanced translocation/inversion carrier couples. Among them, 90 women had a history of spontaneous abortion(≥2 times), stillbirth, fetal multiple malformations, or giving birth to children with chromosome abnormality disease and the peripheral blood karyotyping and fluorescence in situ hybridization testing confirmed that one partner was balanced translocation/inversion carrier. The present pregnancies of these cases were spontaneous and lasted until 18-25 weeks. The other 27 cases were confirmed by chromosome examination at the present pregnancy after the indication of fetal structural abnormalities by fetal karyotyping due to advanced maternal age and abnormal ultrasound and prenatal screening results. The results of karyotyping and CMA by amniocentesis during 18 to 25 gestational weeks were all summarized and described. Results:The successful rate of both methods was 100.0% (117/117). Unbalanced and balanced translocation/inversion were detected in seven (6.0%) and 39 (33.3%) fetuses by karyotyping, respectively. CMA revealed 14 fetuses with pathogenic copy number variation (CNV) and one with variants of uncertain significance(VUS), with an anomaly detection rate of 12.8% (15/117). Among the 15 cases with CNV, 13 were related to the parental translocation/inversion, one with de novo mutation (22q11.2 microdeletion syndrome), and one Duchenne muscular dystrophy mutation carrier. Based on the results of karyotype and CMA, there were 12 fetuses with unbalanced chromosomal fragments (10.3%), 37 fetuses with balanced translocation/inversion (31.6%), and 68 fetuses with normal chromosomes (58.1%). Conclusions:The combination of karyotyping and CMA can provide more accurate prenatal genetic diagnosis when one of a couple carries balanced chromosomal translocations/inversion.

Genetic analysis of 21 fetuses with high suspicion of congenital skeletal malformation by prenatal ultrasound / 中华围产医学杂志

Objective:To explore the genetic etiology of fetuses with high suspicion of congenital skeletal malformation detected by prenatal ultrasound.Methods:This retrospective study collected 21 pregnant women with highly suspected fetal skeletal malformation indicated by ultrasound (the couples had no skeletal malformation) at Institute of Medical Genetics, Henan Provincial People's Hospital from January 2019 to August 2020. Amniotic fluid/umbilical cord blood of the fetus and peripheral blood of the couples were obtained for karyotype analysis, chromosomal microarray analysis, and whole-exome sequencing. Sanger sequencing was performed for the "pathogenic" "suspected pathogenic" "variants of uncertain significance" variants detected by whole exome sequencing. Genetic etiology of the 21 fetuses was described.Results:A total of five chromosomal abnormalities were detected, including four cases of trisomy 21 and one trisomy 18. Chromosome microarray analysis detected one case of abnormal copy number variation, 16 p11.2 microdeletion syndrome. Ten cases of monogenic diseases were found by whole exome sequencing and eight genes were involved ( SGMS2, FGFR3, DYNC2H1, WDR35, TBX5, COL2A1, FGFR2, and ALPL). Totally, 14 variations were detected, among which seven were novel variations (c.8129T>A, c.7126G>A, c.10307_10320del, and c.2641G>T in DYNC2H1 gene; c.3085G>A and c.491G>A in WDR35 gene; c.1070G>T in COL2A1 gene). Conclusions:For fetus, whose parents have no skeletal malformation, highly suspected of congenital malformation of skeletal system by prenatal ultrasound, genetic factor is the primary reason, including chromosomal abnormalities, copy number variations, and monogenic mutations.

Detection rate and clinical significance of regions of homozygosity in prenatal genetic diagnosis / 中华妇产科杂志

Objective:To detect the incidence and analyze the clinical significance of regions of homozygosity (ROH) through the single nucleotide polymorphism array (SNP array).Methods:The SNP array detection results of 5 116 pregnant women in the Third Affiliated Hospital of Guangzhou Medical University from January 2016 to December 2020 were retrospectively analyzed. The pregnant women with ROH (5 Mb as the threshold) were followed up to analyze the relationship between ROH and abnormal fetal phenotype. Whole exon sequencing was performed in 4 cases of consanguineous marriage to detect potential recessive causative genes in the ROH region.Results:(1) A total of 39 cases of ROH were detected, with a positive rate of 0.76% (39/5 116). Among them, 25 cases (64%, 25/39) were detected only on single chromosome, and chromosome 11 had the highest detection rate, suggesting the risk of uniparental disomy; fourteen cases (36%,14/39) were detected on multiple chromosomes, most commonly on chromosomes 11, 1, 3, 4 and 8. (2) The number of cases and detection rate of ROH detected by different prenatal diagnosis indicators were as follows: 12 cases (1.78%, 12/676) in pregnant women with abnormal non-invasive prenatal testing result, 12 cases (0.37%, 12/3 284) in pregnant women with ultrasound abnormality, 4 cases (4/4) in pregnant women with consanguineous marriage, 3 cases (0.92%, 3/326) in pregnant women with previous adverse pregnancy, 2 cases (1.15%, 2/174) in pregnant women with high risk of serology in screening, 2 cases (4.00%, 2/50) in pregnant women with abnormal fetal chromosomal karyotype, 2 cases (0.79%, 2/253) in pregnant women with advanced maternal age, 1 case (0.56%, 1/178) in pregnant women with related parental genetic factors and 1 case (0.58%, 1/171) in pregnant women with the other factors. (3) The follow-up results of 39 cases of prenatal ROH showed that there were 16 cases of term birth, 15 cases of termination of pregnancy, 2 cases of preterm births, 1 case of fetal death and 5 cases lost to follow-up.Conclusions:Chromosomal ROH phenomenon is not rare. By analyzing the detection rate of ROH in prenatal diagnosis, combined with the results of fetal phenotype and postpartum follow-up, the clinical characteristics of ROH are discussed, so as to better understand the relationship between ROH and its phenotype.

Prenatal diagnosis and clinical outcomes of 297 fetuses with conotruncal defects / 中华妇产科杂志

Objective:To analyze the prenatal diagnosis results and pregnancy outcomes of conotruncal defects (CTD) fetuses, and to explore the correlation between the CTD and chromosome diseases.Methods:A total of 297 cases of invasive prenatal diagnosis and chromosome analysis were collected at the Prenatal Diagnosis Center of Guangzhou Women and Children′s Medical Center due to CTD from January 1st, 2011 to December 31th, 2019. According to ultrasonic diagnosis, CTD fetuses were divided into 6 subtypes: tetralogy of Fallot (109 cases), pulmonary atresia (30 cases), transposition of the great arteries (77 cases), double outlet right ventricle (53 cases), truncus arteriosus (14 cases) and interrupted aortic arch (14 cases). According to whether they were combined with intracardiac or extracardiac abnormalities, they were divided into simple group (134 cases), combined with other intracardiac abnormalities group (86 cases), combined with extracardiac abnormalities group (20 cases), combined with intracardiac and extracardiac abnormalities group (37 cases) and only combined with ultrasound soft marker group (20 cases), the last 4 groups were referred as non-simple types. The chromosome test results and pregnancy outcomes of each type and group were analyzed retrospectively.Results:Among the 297 CTD fetuses, the chromosome abnormality rate was 17.5% (52/297). There were 21 cases of abnormal chromosome number, 28 cases of pathogenetic copy number variantions and 3 cases of mosaics. All the 19 cases of micropathogenic fragments smaller than 5 Mb were detected by chromosomal microarray analysis (CMA). Among all the subtypes of CTD, the chromosomal abnormality rate of truncus arteriosus was the highest, at 7/14; while the rate of transposition of the great arteries was the lowest, at 5.2% (4/77). There were significant differences in the rate of chromosomal abnormalities between simple and non-simple types [10.4% (14/134) vs 23.3% (38/163); χ2 =8.428, P=0.004]. In each group, the chromosomal abnormality rate was the highest in the combined with intracardiac and extracardiac abnormalities group, at 37.8% (14/37), and the lowest in the simple group, at 10.4% (14/134). There was no significant difference in the rate of chromosomal abnormalities in all subtypes of simple group (all P>0.05). Among 112 cases of live birth, 1 case was 22q11.2 microdeletion syndrome, 5 cases of postnatal clinical diagnosis and prenatal ultrasound diagnosis were not completely consistent, 5 cases died after birth. Conclusions:The incidence of chromosomal abnormalities is high in fetuses with CTD. CTD fetuses with concurrent extrapardiac malformations are more likely to incorporate chromosomal abnormalities. CMA technology could be used as a first-line genetic detection method for CTD. After excluding chromosomal abnormalities, most of the children with CTD have good prognosis.

Prenatal genetic diagnosis of the fetuses with isolated corpus callosum abnormality / 中华妇产科杂志

Objective:To explore the application value of chromosome karyotype analysis, chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in prenatal diagnosis of isolated corpus callosum abnormality (CCA) fetus.Methods:Fetuses diagnosed with isolated CCA by ultrasound and MRI and receiving invasive prenatal diagnosis in Guangzhou Women and Children′s Medical Center and Qingyuan People′s Hospital from January 2010 to April 2021 were selected. Karyotype analysis and/or CMA [or copy number variation sequencing (CNV-seq)] were performed on all fetal samples, and WES was performed on fetal samples and their parents whose karyotype analysis and/or CMA (or CNV-seq) results were not abnormal.Results:Among 65 fetuses with isolated CCA, 38 cases underwent karyotype analysis, and 3 cases were detected with abnormal karyotypes, with a detection rate of 8% (3/38). A total of 49 fetuses with isolated CCA underwent CMA (or CNV-seq) detection, and 6 cases of pathogenic CNV were detected, the detection rate was 12% (6/49). Among them, the karyotype analysis results were abnormal, and the detection rate of further CMA detection was 1/1. The karyotype results were normal, and the detection rate of further CMA (or CNV-seq) detection was 14% (3/21). The detection rate of CMA as the first-line detection technique was 7% (2/27). A total of 25 fetuses with isolated CCA with negative results of karyotyping and/or CMA were tested by WES, and 9 cases (36%, 9/25) were detected with pathogenic genes. The gradient genetic diagnosis of chromosomal karyotyping, CMA and WES resulted in a definite genetic diagnosis of 26% (17/65) of isolated CCA fetuses.Conclusions:Prenatal genetic diagnosis of isolated CCA fetuses is of great clinical significance. The detection rate of CMA is higher than that of traditional karyotyping. CMA detection could be used as a first-line detection technique for fetuses with isolated CCA. WES could increase the pathogenicity detection rate of fetuses with isolated CCA when karyotype analysis and/or CMA test results are negative.

Genetic characteristics and prognostic analysis of 162 fetal cardiac abnormalities / 中华妇产科杂志

Objective:To analyze the type and characteristics of fetal cardiac abnormalities and their relationships with genetic abnormalities and clinical prognosis.Methods:The clinical data of 162 pregnant women with fetal cardiac abnormalities who came to the prenatal diagnosis center of Peking University First Hospital and performed genetic tests from February 2013 to February 2021 were reviewed. Genetic testing methods included chromosome karyotype analysis, array-based comparative genomic hybridization (aCGH) and pathogenic gene detection. Fetuses with isolated cardiac abnormalities and no fatal genetic abnormalities were assessed using the fetal cardiac birth defects clinical outcome score and followed up.Results:(1) Ultrasonography results: among the 162 fetuses, 86 cases (53.1%, 86/162) had isolated cardiac abnormalities, and 76 cases (46.9%, 76/162) had extra-cardiac abnormalities; single cardiac abnormalities were in 84 (51.9%,84/162) cases, and multiple cardiac abnormalities occurred in 78 cases (48.1%,78/162). (2) Genetic examination results: there were 39 cases (24.1%, 39/162) of pathogenic genetic abnormalities, including 35 cases (21.6%, 35/162) of pathogenic chromosome karyotype abnormality, 3 cases (1.9%, 3/162) of pathogenic copy number variant (CNV), and 1 case (0.6%, 1/162) of pathogenic gene variation. The detection rates of pathogenic genetic abnormalities were 16.3% (14/86) in fetuses with isolated cardiac abnormalities and 32.9% (25/76) in fetuses with cardiac abnormalities and extra-cardiac abnormalities, and the difference was statistically significant ( χ2=6.094, P=0.014). The detection rate of genetic abnormalities was 28.6% (24/84) in the single cardiac abnormalities, among which ventricular septal defect was 36.7% (11/30), atrioventricular septal defect was 8/13, tetralogy of Fallot was 3/17, persistent trancus arteriosus was 1/1, cardiac tumor was 1/1; no genetic abnormality was detected in the other single cardiac abnormality types (22 cases in total). The main types of pathogenic genetic abnormalities were trisomy 21 (41.7%, 10/24) and trisomy 18 (41.7%, 10/24). (3) Pregnancy outcome and fetal prognosis: among 72 fetuses with isolated heart abnormalities without pathogenic genetic abnormalities, there were 4 cases of grade Ⅰ, all of which continued pregnancy; 39 cases of grade Ⅱ, with 21 cases induced labor, 18 cases continued pregnancy; 26 cases of grade Ⅲ, with 23 cases induced labor, 3 cases continued pregnancy; 3 cases of grade Ⅳ, all of which induced labor. Totally, there were 47 cases induced labor and 25 cases continued pregnancy, 24 cases (96.0%, 24/25) of which were alive. Conclusions:When fetal cardiac abnormalities are detected by prenatal ultrasound, comprehensive cardiac and extra-cardiac ultrasound assessment and further genetic testing are recommended. Fetuses excluded pathogenic genetic abnormalities and extra-cardiac abnormalities should perform clinical prognostic score evaluation through multidisciplinary collaboration, to improve maternal and fetal outcomes.

Value of chromosomal microarray analysis for genetic evaluation of fetal ultrasound abnormality / 中国辐射卫生

Objective To evaluate the value of chromosomal microarray analysis (CMA) for genetic evaluation of fetal ultrasound abnormality. Methods A total of 180 pregnant women with fetal abnormality detected by prenatal ultrasound diagnosis in the first trimester during the period from January 2020 through May 2022 were enrolled as the study subjects. All prenatal fetal screening samples were subjected to G-band karyotyping and CMA. Results G-band karyotyping detected normal karyotypes in 168 samples (93.85%) and abnormal karyotypes in 11 samples (6.15%), and CMA detected 17 positive samples (9.44%) and 163 negative samples (90.56%). The seventeen positive samples included 11 pathogenic copy number variations (CNVs) and 6 variants of unknown significance (VOUS), and there were 11 CMA-positive results consistent with G-band karyotyping, and 6 additional pathogenic CNVs mainly included microdeletion and microduplication syndromes. The detection rates of pathogenic CNVs were 11.11%, 2.63%, 2.78%, 4.00%, 0, 0, 11.11% and 0 among the fetuses with abnormal structure of the cardiovascular system, the lymphatic system, the nervous system, the digestive system, the cranial and face system, the skeletal system, the urinary system, and other system (χ2 =8.188, P = 0.316). All eleven fetuses with pathogenic CNVs detected by CMA were all induced for abortion. Conclusion CMA improves the detection of genetic abnormality among fetuses with ultrasound abnormality in relative to G-band karyotyping, which is feasible for prenatal cytogenetic diagnosis among fetuses with ultrasound abnormality

Prenatal genetic features and prognostic factors in monochorionic twins with twin reversed arterial perfusion sequence / 中华围产医学杂志

Objective:To investigate the prenatal genetic features and the factors influencing the prognosis of twin reversed arterial perfusion sequence (TRAPS) in monochorionic twin pregnancies.Methods:A total of 99 cases diagnosed with TRAPS by prenatal ultrasound in the First Affiliated Hospital of Sun Yat-sen University from July 1, 2007, to December 31, 2021, were included retrospectively. The prenatal genetic features of acardiac and pump twins were analyzed. Eighty-nine cases were followed up and divided into two groups: the expectation group ( n=45) and the intrauterine intervention group (all underwent radiofrequency ablation, n=44) and the pregnancy outcomes were compared between the two groups. After excluding eight cases without complete ultrasound data, the expectation group was further divided into two subgroups: the pump fetus survival ( n=28) and the pump fetus death groups ( n=9), and the survival subgroup was divided into the spontaneous arrest group ( n=16) and coexistence group ( n=12) according to whether or not the blood flow stopped spontaneously.The relationship between ultrasonic indexes and pregnancy outcome was compared between the groups. Chi-square test (or Fisher's exact test), univariate logistic regression analysis and receiver operating characteristic (ROC) curve were used to analyze the relationship between the estimated acardiac to pump twin weight ratio (A/P Wt) and the pregnancy outcome of the pump twin in the expectation group. Results:(1) The median gestational age at diagnosis of the 99 TRAPS cases was 16.4 weeks (13.3- 21.3 weeks) and 32% (32/99) were diagnosed in the first trimester. Most of the cases were monochorionic diamniotic pregnancies (72/99, 73%). The survival rate of the pump twins was 71% (63/89). (2) Chromosome karyotyping and/or chromosomal microarray analysis was performed in 19 acardiac twins and 82 pump twins. The detection rate of genetic abnormalities in the acardiac twins was higher than that in the pump twins [4/19 vs 5% (4/82), Fisher's exact test, P=0.039]. Chromosomal microarray analysis was performed in 54 pump twins with normal karyotypes and the results showed three (6%) with genetic abnormalities. (3) In the expectation group, the area under ROC curve for the prenatal A/P Wt were 0.913 in predicting pump twin death and 0.807 in predicting spontaneous cessation of blood flow in the cardiac twin, and the cut-off values were 0.24 (sensitivity: 88.9%, specificity: 96.4%) and 0.11 (sensitivity: 75.0%, specificity: 81.3%), respectively. The survival rate of pump twins with abnormal cardiac function after intrauterine intervention was higher than that of the expectant group [72% (18/25) vs 3/11, Fisher's exact test, P=0.025]. Conclusions:TRAPS can be diagnosed in the first trimester and commonly occur in monochorionic diamniotic pregnancies. The detection rate of genetic abnormalities in the acardiac twins is higher than that in the pump twins. Prenatal A/P Wt>0.24 indicates the death of the pump twin and prenatal A/P Wt≤0.11 suggests a high possibility of spontaneous cessation of blood flow in the acardiac twin. Radiofrequency ablation is an effective method for improving the prognosis of the pump twin with cardiac dysfunction.

Phenotype analysis of 11 fetuses with 22q11.2 microduplication diagnosed prenatally / 中华全科医师杂志

Objective:To analyze the clinical phynotypes of fetuses with 22q11.2 microduplications.Method:Eleven fetuses were diagnosed with 22q11.2 microduplications among 2 969 cases who underwent prenatal chromosomal microarray analysis from January 2016 to February 2020. The phenotypes, indications for invasive prenatal diagnosis, genetic results, pregnancy outcomes and postnatal clinical presentation were analyzed.Results:There were 6 cases diagnosed with classic 3.0 Mb microduplication (DiGeorge and velocardiofacial syndromes, DGS/VCFS) in the 22q11.2, 1 case with 1.5 Mb proximal microduplication and 4 cases with distal small segment microduplication (E-H). Out of 11 fetuses with 22q11.2 microduplications,7 cases were inherited, 2 cases was de novo and data were not available for 2 cases. Vicular septal defect and anencephalu were diagnosed by ultrasonography in 2 cases,fetal growth restriction was diagnosed in 2 cases,no any abnormalities were found in remaining 7 cases. Seven cases(3 cases of classic 3.0 Mb microduplication, 1 case of proximal microduplication and 3 cases of distal small segment microduplication) were delivered at full-term;and pregnancy was terminated in 4 cases. Seven infants were followed up after birth, 4 infants were normal, 3 showed abnormal phenotypes.Conclusion:The clinical phenotypes after birth of fetuses with 22q11.2 microduplication are diverse. Prenatal genetic counseling is necessary,so that pregnant women and their families can fully understand the possible clinical phenotypes and make informed choices.