Analysis of copy number variations and possible candidate genes in spontaneous abortion by copy number variation sequencing.

Introduction: Embryonic chromosomal abnormalities represent a major causative factor in early pregnancy loss, highlighting the importance of understanding their role in spontaneous abortion. This study investigates the potential correlation between chromosomal abnormalities and spontaneous abortion using copy number variation sequencing (CNV-seq), a Next-Generation Sequencing (NGS) technology. Methods: We analyzed Copy Number Variations (CNVs) in 395 aborted fetal specimens from spontaneous abortion patients by CNV-seq. And collected correlated data, including maternal age, gestational week, and Body Mass Index (BMI), and analyzed their relationship with the CNVs. Results: Out of the 395 cases, 67.09% of the fetuses had chromosomal abnormalities, including numerical abnormalities, structural abnormalities, and mosaicisms. Maternal age was found to be an important risk factor for fetal chromosomal abnormalities, with the proportion of autosomal trisomy in abnormal karyotypes increasing with maternal age, while polyploidy decreased. The proportion of abnormal karyotypes with mosaic decreased as gestational age increased, while the frequency of polyploidy and sex chromosome monosomy increased. Gene enrichment analysis identified potential miscarriage candidate genes and functions, as well as pathogenic genes and pathways associated with unexplained miscarriage among women aged below or over 35 years old. Based on our study, it can be inferred that there is an association between BMI values and the risk of recurrent miscarriage caused by chromosomal abnormalities. Discussion: Overall, these findings provide important insights into the understanding of spontaneous abortion and have implications for the development of personalized interventions for patients with abnormal karyotypes.

[Clinical characterization of girls with Turner syndrome]. / Caracterización de una cohorte de pacientes pediátricas con Síndrome de Turner.

Turner syndrome is a genetic disorder that occurs in women with partial or complete absence of an X chromosome. OBJECTIVE: To describe the clinical, laboratory, and genotypic characteristics of patients with Turner syndrome, treated at three health institutions in Medellin. PATIENTS AND METHOD: A retrospective study was carried out. A total of 97 patients with Turner syndrome (< 18 years) confirmed by karyotype between 2011 and 2018 were included. Patients whose karyotype did not meet the specification of the American College of Medical Genetics were excluded. Data on sociodemographic details, nutritional variables, phenotypic characteristics, and laboratory tests were collected. A descriptive analysis was performed in SPSS software version 20. RESULTS: Median age at diagnosis was 8.5 years (IQR 4-12). The main clinical characteristic was short stature (90%). Additionally, they presented cardiovascular malformations (35%), renal alterations (26%), hearing disorders, mainly hypoacusis (33%), and neuropsychiatric disorders (44%). The most frequent karyotype was 45,X (51%) followed by 45,X/46,XX (14%). The patients with 45,X karyotype had the most classic clinical characteristics. Patients > 5 years old had a higher proportion of weight excess than the general population. Dyslipidemia was found in 62% and hypothyroidism in 22%. 70% of patients > 11 years received pubertal induction; 23% presented spontaneous puberty and 44% of them required hormonal maintenance. 86% received somatropin. CONCLUSION: The patients with Turner syndrome in our study presented a high frequency of short stature and cardiovascular, renal, hearing, endocrine, and neuropsychiatric comorbidities. The diagnosis was delayed due to the lack of clinical suspicion given its variable presentation.

In Tandem Intragenic Duplication of Doublesex and Mab-3-Related Transcription Factor 1 (DMRT1) in an SRY-Negative Boy with a 46,XX Disorder of Sex Development.

Disorders of sexual development (DSDs) encompass a group of congenital conditions associated with atypical development of internal and external genital structures. Among those with DSDs are 46,XX males, whose condition mainly arises due to the translocation of SRY onto an X chromosome or an autosome. In the few SRY-negative 46,XX males, overexpression of other pro-testis genes or failure of pro-ovarian/anti-testis genes may be involved, even if a non-negligible number of cases remain unexplained. A three-year-old boy with an SRY-negative 46,XX karyotype showed a normal male phenotype and normal prepubertal values for testicular hormones. A heterozygous de novo in tandem duplication of 50,221 bp, which encompassed exons 2 and 3 of the Doublesex and Mab-3-related transcription factor 1 (DMRT1) gene, was detected using MPLA, CGH-array analysis, and Sanger sequencing. Both breakpoints were in the intronic regions, and this duplication did not stop or shift the coding frame. Additional pathogenic or uncertain variants were not found in a known pro-testis/anti-ovary gene cascade using a custom NGS panel and whole genome sequencing. The duplication may have allowed DMRT1 to escape the transcriptional repression that normally occurs in 46,XX fetal gonads and thus permitted the testicular determination cascade to switch on. So far, no case of SRY-negative 46,XX DSD with alterations in DMRT1 has been described.

Male refractory hypospadias with sexual reversal: a case report.

BACKGROUND: Hypospadias is one of the most prevalent urogenital malformations in clinic. However, some hypospadias may have a more complex disorder of sex development. Usually, hypospadias in these patients is severe. Among them, the 46,XX male sex reversal syndrome is a rare disorder of sex development, and this may be the main reason for this type of hypospadias being difficult to repair. CASE PRESENTATION: We present a Han nationality 19-year-old male with failure of repeated repair of hypospadias. No sperm was found on semen analysis. Lingual mucosal graft was carried out for this patient. It still did not succeed after using lingual mucosal graft repair. Karyotype analysis of this patient confirmed 46,XX karyotype. CONCLUSION: Hypospadias with 46,XX male sex reversal syndrome is hard to repair. Chromosome karyotype examination in patients with hypospadias is suggested. Genetic testing is recommended. In the future, further research is needed on the pathogenesis of disease and how to treat and prevent it.

45,X/46,XX at the first amniocentesis, and 45,X/47,XXX/46,XX at the repeat amniocentesis and at birth in a pregnancy associated with a favorable fetal outcome, perinatal progressive decrease of the 45,X cell line and cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes.

OBJECTIVE: We present 45,X/46,XX at the first amniocentesis, and 45,X/47,XXX/46,XX at the repeat amniocentesis and at birth in a pregnancy associated with a favorable fetal outcome, perinatal progressive decrease of the 45,X cell line and cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes. CASE REPORT: A 43-year-old, gravida 3, para 1, woman underwent amniocentesis at 18 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 45,X[4]/46,XX[20]. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed arr (X) × 3 [0.24], consistent with 24% mosaicism for triple X. Repeat amniocentesis at 20 weeks of gestation revealed the result of 45,X[17]/47,XXX[8]/46,XX[121]. She was referred for genetic counseling, and the third amniocentesis performed at 30 weeks of gestation revealed the result of 45,X[3]/47,XXX[2]/46,XX[16]. The mother had a karyotype of 46,XX. aCGH analysis on the DNA extracted from uncultured amniocytes showed arr Xp22.33q28 × 2.2 (log2 ratio = 0.15), consistent with 20% mosaicism for triple X. Interphase fluorescence in situ hybridization (FISH) analysis on 100 uncultured amniocytes showed that 11 cells (11%) were monosomy X, seven cells (7%) were triple X, and the others were disomy X. At 39 weeks of gestation, a 3,620-g phenotypically normal female baby was delivered without any phenotypic abnormality. The karyotypes of cord blood, umbilical cord and placenta were 47,XXX[7]/45,X[1]/46,XX[32], 47,XXX[13]/46,XX[27] and 47,XXX[2]/46,XX[38], respectively. When follow-up at age one month, the neonate was phenotypically normal, and FISH analysis on 106 buccal mucosal cells showed that eight cells (7.5%) were monosomy X, seven cells (6.6%) were triple X, and the others were disomy X. CONCLUSION: Mosaic 45,X/46,XX at amniocentesis may be in fact mosaic 45,X/47,XXX/46,XX and can be associated with a favorable fetal outcome and perinatal progressive decrease of the 45,X cell line.

Perinatal detection of disomy X cell line by fluorescence in situ hybridization in a pregnancy with 45,X/47,XXX at amniocentesis, cytogenetic discrepancy in various tissues and a favorable outcome.

OBJECTIVE: We present perinatal detection of disomy X cell line by fluorescence in situ hybridization (FISH) in a pregnancy with 45,X/47,XXX at amniocentesis, cytogenetic discrepancy in various tissues and a favorable outcome. CASE REPORT: A 34-year-old, gravida 3, para 1, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 45,X[22]/47,XXX[10]. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed the result of arr (X) × 1-2, (1-22) × 2, consistent with 32% mosaicism for monosomy X. She was referred for genetic counseling at 19 weeks of gestation. Prenatal ultrasound findings and parental karyotypes were normal. Repeat amniocentesis at 29 weeks of gestation revealed a karyotype of 45,X[36]/47,XXX[4] (Fig. 1) in cultured amniocytes. Simultaneous molecular analysis on uncultured amniocytes revealed the result of arr (1-22) × 2, Y × 0 by aCGH with no genomic imbalance, and 15% (15/100 cells) mosaicism for disomy X, 61% (61/100 cells) mosaicism for monosomy X and 24% (24/100 cells) mosaicism for triple X by interphase fluorescence in situ hybridization (FISH) analysis. The pregnancy was encouraged to continue and at 37 weeks of gestation, a 2834-g phenotypically normal female baby was delivered. The karyotypes of cord blood, umbilical cord and placenta were 45,X[33]/47,XXX[7], 45,X[30]/47,XXX[10] and 47,XXX[38]/45,X[2], respectively. When follow-up at age three months, the neonate was normal in development. FISH analysis on 99 buccal mucosal cells showed 49% (48/99 cells) mosaicism for monosomy X, 8% (8/99 cells) mosaicism for triple X and 43% (42/99 cells) mosaicism for disomy X (Fig. 2). Peripheral blood had a karyotype of 45,X[38]/47,XXX[2]. When follow-up at age nine months, the neonate was normal in development. FISH analysis on 102 buccal mucosal cells showed 11% (11/102 cells) mosaicism for monosomy X, 12% (12/102 cells) mosaicism for triple X and 77% (79/102 cells) mosaicism for disomy X. Peripheral blood had a karyotype of 45,X[30]/47,XXX[10]. CONCLUSION: 45,X/47,XXX at amniocentesis may detect disomy X cell line by FISH analysis and can be associated with postnatal progressive decrease of the aneuploid cell lines, increase of the disomy X cell line and a favorable outcome.

Low-level mosaic trisomy 21 at amniocentesis in a pregnancy associated with cytogenetic discrepancy in various tissues, perinatal progressive decrease of the trisomy 21 cell line and a favorable fetal outcome.

OBJECTIVE: We present low-level mosaic trisomy 21 at amniocentesis in a pregnancy associated with cytogenetic discrepancy in various tissues, perinatal progressive decrease of the trisomy 21 cell line and a favorable fetal outcome. CASE REPORT: A 36-year-old, gravida 2, para 1, woman underwent amniocentesis at 18 weeks of gestation because of advanced maternal age, and the result was 47,XY,+21 [8]/46,XY [26]. Prenatal ultrasound findings were unremarkable. She was referred for genetic counseling, and repeat amniocentesis performed at 23 weeks of gestation revealed the result of 47,XY,+21 [3]/46,XY [21]. The parental karyotypes were normal. At repeat amniocentesis, quantitative fluorescent polymerase chain reaction (QF-PCR) analysis using the DNA extracted from uncultured amniocytes and parental bloods excluded uniparental disomy (UPD) 21, array comparative genomic hybridization (aCGH) analysis on uncultured amniocytes revealed the result of arr 21q11.2q22.3 × 2.4, consistent with 40% mosaicism for trisomy 21, and fluorescence in situ hybridization (FISH) analysis on uncultured amniocytes revealed 67% (67/100 cells) mosaicism for trisomy 21. The woman was advised to continue the pregnancy, and a 1370-g male baby was delivered prematurely at 29 weeks of gestation without phenotypic abnormalities. The karyotypes of umbilical cord and placenta were 47,XY,+21 [13]/46,XY [27] and 47,XY,+21 [40], respectively. QF-PCR determined maternal origin of the extra chromosome 21 of trisomy 21 in the placenta. When follow-up at age 8½ months, the neonate was normal in appearance and development. The peripheral blood had a karyotype of 47,XY,+21 [1]/46,XY [39], and FISH analysis on buccal mucosal cells showed 9.7% (11/113 cells) mosaicism for trisomy 21, compared with 2% (2/100 cells) in the normal control. CONCLUSION: Low-level mosaic trisomy 21 at amniocentesis can be associated with cytogenetic discrepancy in various tissues, perinatal progressive decrease of the trisomy 21 cell line and a favorable fetal outcome.

Low-level mosaic trisomy 21 at amniocentesis in a pregnancy associated with cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes, perinatal progressive decrease of the aneuploid cell line and a favorable fetal outcome.

OBJECTIVE: We present low-level mosaic trisomy 21 at amniocentesis in a pregnancy with a favorable fetal outcome. CASE REPORT: A 34-year-old, primigravid woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XY,+21 [7]/46,XY [33]. At 23 weeks of gestation, repeat amniocentesis revealed a karyotype of 47,XY,+21 [4]/46,XY [22], and cord blood sampling revealed the karyotype of 47,XY,+21 [5]/46,XY [35]. The parental karyotypes were normal. Quantitative fluorescent polymerase chain reaction (QF-PCR) analysis on uncultured amniocytes and parental bloods excluded UPD 21, array comparative genomic hybridization (aCGH) analysis on uncultured amniocytes revealed the result of arr 21q11.2q22.3 × 2.3, consistent with 30% mosaicism for trisomy 21. Interphase fluorescence in situ hybridization (FISH) analysis on uncultured amniocytes revealed 43.8% (35/80 cells) mosaicism for trisomy 21. The woman was advised to continue the pregnancy, and a phenotypically normal 3,340-g male baby was delivered at 39 weeks of gestation. The cord blood had a karyotypes of 46,XY (40/40 cells). QF-PCR on placenta showed mosaic trisomy 21. When follow-up at age three months, the neonate was normal in phenotype and development. FISH analysis on buccal mucosal cells showed 9% (10/101 cells) mosaicism for trisomy 21, compared with 0% (0/100 cells) in the normal control. CONCLUSION: Low-level mosaic trisomy 21 at amniocentesis can be associated with cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes, perinatal progressive decrease of the aneuploid cell line and a favorable fetal outcome.

[Genetic analysis of a child with mosaicism Turner syndrome].

OBJECTIVE: To explore the genetic characteristics of a child with mosaicism Turner syndrome. METHODS: A child who had presented at Linyi People's Hospital on May 19, 2022 due to short stature was selected as the study subject. The child was subjected to combined chromosomal karyotyping, fluorescence in situ hybridization (FISH), and chromosomal microarray analysis (CMA). RESULTS: The child was found to have a 46,X,i(X)(q10)[94]/45,X[6] karyotype. The result of FISH was nucish(XYpter,XYqter)1[78]/(XYpter)1,(XYqter)3[122]. CMA result for her peripheral blood sample was arr[hg19]Xp22.33p11.1(168551_58526888)×1, and that for her oral mucosal cells was arr[hg19]Xp22.33p11.1(168551_58526888)1-2,Xq11.2q28(63000001_155233098)×2-3. By integrating the above findings, her molecular karyotype was determined as mos 46,X,i(X)(q10)[94]/45,X[6].arr[hg19]Xp22.33p11.1(168551_58526888)×1-2,Xq11.2q28(63000001_155233098)×2-3.nucish(XYpter)1,(XYqter)3[122]/(XYpter,XYqter)1[78], which has indicated mosaicism Turner syndrome. CONCLUSION: The 46,X,i(X)(q10)/45,X mosaicism probably underlay the pathogenesis in this child.

Chromosome microarray analysis combined with karyotype analysis is a powerful tool for the detection in pregnant women with high-risk indicators.

BACKGROUND: Karyotype analysis and fluorescence in situ hybridization (FISH) are commonly used for prenatal diagnosis, however they have many disadvantages. Chromosome microarray analysis (CMA) has the potential to overcome these disadvantages. This study aimed to evaluate the clinical value of CMA in the diagnosis of fetal chromosomal anomalies in southwest of China. METHODS: A total of 3336 samples of amniotic fluid or umbilical cord blood from pregnant women with high-risk indicators at our center in southwest of China from June 2018 to January 2023 were included in the retrospective analysis. 3222 cases tested by CMA and karyotyping, 114 cases only tested by CMA. RESULTS: 3336 samples divided into 2911 cases with single and 425 cases with multiple high-risk indicators. The aneuploidy and pathogenic/likely pathogenic copy number variations (CNVs) of 2911 cases with single high-risk indicator were 4.43% (129/2911) and 2.44% (71/2911) respectively; the aneuploidy and pathogenic/likely pathogenic CNVs of 425 cases with multiple high-risk indicators were 6.82% (29/425) and 2.12% (9/425) respectively. The rate of aneuploidy increased significantly with pregnancy age or NT value. The detection rate of aneuploidy on cases with AMA combined NT ≥ 2.5 mm was significantly higher than that in cases only with AMA (p < 0.001); the detection rate of aneuploidy and pathogenic/likely pathogenic CNVs in cases with AMA combined NIPT high-risk were higher than that in cases only with AMA (p < 0.001, p < 0.05). CONCLUSIONS: The combined application of CMA and karyotyping were recommended in prenatal diagnosis for providing a scientific and accurate genetic diagnosis and improving the quality of prenatal genetic counseling.

Comparative chromosome painting in three Pelecaniformes species (Aves): Exploring the role of macro and microchromosome fusions in karyotypic evolution.

Pelecaniformes is an order of waterbirds that exhibit diverse and distinct morphologies. Ibis, heron, pelican, hammerkop, and shoebill are included within the order. Despite their fascinating features, the phylogenetic relationships among the families within Pelecaniformes remain uncertain and pose challenges due to their complex evolutionary history. Their karyotypic evolution is another little-known aspect. Therefore, to shed light on the chromosomal rearrangements that have occurred during the evolution of Pelecaniformes, we have used whole macrochromosome probes from Gallus gallus (GGA) to show homologies on three species with different diploid numbers, namely Cochlearius cochlearius (2n = 74), Eudocimus ruber (2n = 66), and Syrigma sibilatrix (2n = 62). A fusion between GGA6 and GGA7 was found in C. cochlearius and S. sibilatrix. In S. sibilatrix the GGA8, GGA9 and GGA10 hybridized to the long arms of biarmed macrochromosomes, indicating fusions with microchromosomes. In E. ruber the GGA7 and GGA8 hybridized to the same chromosome pair. After comparing our painting results with previously published data, we show that distinct chromosomal rearrangements have occurred in different Pelecaniformes lineages. Our study provides new insight into the evolutionary history of Pelecaniformes and the chromosomal changes involving their macrochromosomes and microchromosomes that have taken place in different species within this order.

Analysis of genetic variability in Turner syndrome linked to long-term clinical features.

Background: Women with Turner syndrome (TS) (45,X and related karyotypes) have an increased prevalence of conditions such as diabetes mellitus, obesity, hypothyroidism, autoimmunity, hypertension, and congenital cardiovascular anomalies (CCA). Whilst the risk of developing these co-morbidities may be partly related to haploinsufficiency of key genes on the X chromosome, other mechanisms may be involved. Improving our understanding of underlying processes is important to develop personalized approaches to management. Objective: We investigated whether: 1) global genetic variability differs in women with TS, which might contribute to co-morbidities; 2) common variants in X genes - on the background of haploinsufficiency - are associated with phenotype (a "two-hit" hypothesis); 3) the previously reported association of autosomal TIMP3 variants with CCA can be replicated. Methods: Whole exome sequencing was undertaken in leukocyte DNA from 134 adult women with TS and compared to 46,XX controls (n=23), 46,XX women with primary ovarian insufficiency (n=101), and 46,XY controls (n=11). 1) Variability in autosomal and X chromosome genes was analyzed for all individuals; 2) the relation between common X chromosome variants and the long-term phenotypes listed above was investigated in a subgroup of women with monosomy X; 3) TIMP3 variance was investigated in relation to CCA. Results: Standard filtering identified 6,457,085 autosomal variants and 126,335 X chromosome variants for the entire cohort, whereas a somatic variant pipeline identified 16,223 autosomal and 477 X chromosome changes. 1) Overall exome variability of autosomal genes was similar in women with TS and control/comparison groups, whereas X chromosome variants were proportionate to the complement of X chromosome material; 2) when adjusted for multiple comparisons, no X chromosome gene/variants were strongly enriched in monosomy X women with key phenotypes compared to monosomy X women without these conditions, although several variants of interest emerged; 3) an association between TIMP3 22:32857305:C-T and CCA was found (CCA 13.6%; non-CCA 3.4%, p<0.02). Conclusions: Women with TS do not have an excess of genetic variability in exome analysis. No obvious X-chromosome variants driving phenotype were found, but several possible genes/variants of interest emerged. A reported association between autosomal TIMP3 variance and congenital cardiac anomalies was replicated.

Optical genome mapping for prenatal diagnosis: A prospective study.

PURPOSE: Cytogenetic analysis provides important information for prenatal decision-making and genetic counseling. Optical genome mapping (OGM) has demonstrated its performances in retrospective studies. In our prospective study, we assessed the quality of DNA obtained from cultures of amniotic fluid (AF) and chorionic villi (CV) and evaluated the ability of OGM to detect all clinically relevant aberrations identified by standard methods. METHODS: A total of 37 prenatal samples from pregnancies with a fetal anomaly on ultrasound were analyzed prospectively by OGM between January 1, 2021 and June 31, 2022. OGM results were interpreted blindly and compared to the results obtained by standard techniques. RESULTS: OGM results were interpretable in 92% of samples. We observed 100% concordance between OGM and karyotype and/or chromosomal microarray results. In addition, OGM identified a median of 30 small (<100 kb) structural variations per case with the involvement of 12 OMIM genes, of which 3 were OMIM morbid genes. CONCLUSION: This prospective study showed OGM performed well in detecting genomic alterations in cell cultures from prenatal samples. The place of OGM in relation to CMA or exome sequencing remains to be defined in order to optimize the prenatal diagnostic procedure.

A novel tetra-primer ARMS-PCR approach for the molecular karyotyping of chromosomal inversion 2Ru in the main malaria vectors Anopheles gambiae and Anopheles coluzzii.

BACKGROUND: Chromosomal inversion polymorphisms have been associated with adaptive behavioral, physiological, morphological and life history traits in the two main Afrotropical malaria vectors, Anopheles coluzzii and Anopheles gambiae. The understanding of the adaptive value of chromosomal inversion systems is constrained by the feasibility of cytological karyotyping. In recent years in silico and molecular approaches have been developed for the genotyping of most widespread inversions (2La, 2Rb and 2Rc). The 2Ru inversion, spanning roughly 8% of chromosome 2R, is commonly polymorphic in West African populations of An. coluzzii and An. gambiae and shows clear increases in frequency with increasing rainfall seasonally and geographically. The aim of this work was to overcome the constraints of currently available cytological and high-throughput molecular assays by developing a simple PCR assay for genotyping the 2Ru inversion in individual specimens of both mosquito species. METHODS: We designed tetra-primer amplification refractory mutation system (ARMS)-PCR assays based on five tag single-nucleotide polymorphisms (SNPs) previously shown to be strongly correlated with 2Ru inversion orientation. The most promising assay was validated against laboratory and field samples of An. coluzzii and An. gambiae karyotyped either cytogenetically or molecularly using a genotyping-in-thousands by sequencing (GT-seq) high-throughput approach that employs targeted sequencing of multiplexed PCR amplicons. RESULTS: A successful assay was designed based on the tag SNP at position 2R, 31710303, which is highly predictive of the 2Ru genotype. The assay, which requires only one PCR, and no additional post-PCR processing other than electrophoresis, produced a clear banding pattern for 98.5% of the 454 specimens tested, which is a 96.7% agreement with established karyotyping methods. Sequences were obtained for nine of the An. coluzzii specimens manifesting 2Ru genotype discrepancies with GT-seq. Possible sources of these discordances are discussed. CONCLUSIONS: The tetra-primer ARMS-PCR assay represents an accurate, streamlined and cost-effective method for the molecular karyotyping of the 2Ru inversion in An. coluzzii and An. gambiae. Together with approaches already available for the other common polymorphic inversions, 2La, 2Rb and 2Rc, this assay will allow investigations of the adaptive value of the complex set of inversion systems observed in the two major malaria vectors in the Afrotropical region.

[Genetic analysis of two cases with MYC "negative" Burkitt lymphoma].

OBJECTIVE: To carry out combined genetic analysis on two patients suspected for Burkitt lymphoma to facilitate their diagnosis and treatment. METHODS: G banded karyotyping and interphase and metaphase fluorescence in situ hybridization (FISH) were used to detect the specific sites of chromosomes by using separate and fusion probes. RESULTS: The separate probe showed no presence of MYC gene abnormality, while fusion probe confirmed the IGH::MYC translocation in the samples. Combined with the clinical features and pathological characteristics, the two patients were finally diagnosed with Burkitt lymphoma, which was confirmed by targeted capture next generation sequencing. CONCLUSION: The separate probe for the MYC gene has some shortcomings and should be used together with dual fusion probe to improve the accuracy of diagnosis.

[Genetic analysis of a Chinese pedigree affected with overgrowth syndrome due to a small supernumerary marker chromosome].

OBJECTIVE: To carry out genetic analysis for a Chinese pedigree affected with intellectual disability and overgrowth due to a supernumerary marker chromosome (sSMC). METHODS: A pedigree which had presented at Jiaxing Maternity and Child Health Care Hospital on August 31, 2021 was selected as the study subject, for which chromosomal karyotyping, single nucleotide polymorphism-based microarray (SNP-array), and fluorescence in situ hybridization (FISH) were carried out in combination. RESULTS: SNP-array analysis showed that the proband and his sister had both harbored a 16.1 Mb duplication which encompassed the critical region of 15q26 overgrowth syndrome. FISH confirmed that the proband was 47,XX,+neo(15)(qter→q25.3:)mat, her mother was 47,XX,del(15)(q25.3:),+neo(15)(qter→q25.3:), whilst her father was normal. CONCLUSION: Application of multiple genetic techniques has facilitated delineation of the origin of sSMC and reliable genetic counseling for this pedigree.

Permission to pass: on the role of p53 as a gatekeeper for aneuploidy.

Aneuploidy-the karyotype state in which the number of chromosomes deviates from a multiple of the haploid chromosome set-is common in cancer, where it is thought to facilitate tumor initiation and progression. However, it is poorly tolerated in healthy cells: during development and tissue homeostasis, aneuploid cells are efficiently cleared from the population. It is still largely unknown how cancer cells become, and adapt to being, aneuploid. P53, the gatekeeper of the genome, has been proposed to guard against aneuploidy. Aneuploidy in cancer genomes strongly correlates with mutations in TP53, and p53 is thought to prevent the propagation of aneuploid cells. Whether p53 also participates in preventing the mistakes in cell division that lead to aneuploidy is still under debate. In this review, we summarize the current understanding of the role of p53 in protecting cells from aneuploidy, and we explore the consequences of functional p53 loss for the propagation of aneuploidy in cancer.

Exploring chromosome evolution in 250 million year old groups of dragonflies and damselflies (Insecta:Odonata).

Using recently published chromosome-length genome assemblies of two damselfly species, Ischnura elegans and Platycnemis pennipes, and two dragonfly species, Pantala flavescens and Tanypteryx hageni, we demonstrate that the autosomes of Odonata have undergone few fission, fusion, or inversion events, despite 250 million years of separation. In the four genomes discussed here, our results show that all autosomes have a clear ortholog in the ancestral karyotype. Despite this clear chromosomal orthology, we demonstrate that different factors, including concentration of repeat dynamics, GC content, relative position on the chromosome, and the relative proportion of coding sequence all influence the density of syntenic blocks across chromosomes. However, these factors do not interact to influence synteny the same way in any two pairs of species, nor is any one factor retained in all four species. Furthermore, it was previously unknown whether the micro-chromosomes in Odonata are descended from one ancestral chromosome. Despite structural rearrangements, our evidence suggests that the micro-chromosomes in the sampled Odonata do indeed descend from an ancestral chromosome, and that the micro-chromosome in P. flavescens was lost through fusion with autosomes.