Human 8-cell embryos enable efficient induction of disease-preventive mutations without off-target effect by cytosine base editor

Approximately 140 million people worldwide are homozygous carriers of APOE4 (ε4), a strong genetic risk factor for late onset familial and sporadic Alzheimer's disease (AD), 91% of whom will develop AD at earlier age than heterozygous carriers and noncarriers. Susceptibility to AD could be reduced by targeted editing of APOE4, but a technical basis for controlling the off-target effects of base editors is necessary to develop low-risk personalized gene therapies. Here, we first screened eight cytosine base editor variants at four injection stages (from 1- to 8-cell stage), and found that FNLS-YE1 variant in 8-cell embryos achieved the comparable base conversion rate (up to 100%) with the lowest bystander effects. In particular, 80% of AD-susceptible ε4 allele copies were converted to the AD-neutral ε3 allele in human ε4-carrying embryos. Stringent control measures combined with targeted deep sequencing, whole genome sequencing, and RNA sequencing showed no DNA or RNA off-target events in FNLS-YE1-treated human embryos or their derived stem cells. Furthermore, base editing with FNLS-YE1 showed no effects on embryo development to the blastocyst stage. Finally, we also demonstrated FNLS-YE1 could introduce known protective variants in human embryos to potentially reduce human susceptivity to systemic lupus erythematosus and familial hypercholesterolemia. Our study therefore suggests that base editing with FNLS-YE1 can efficiently and safely introduce known preventive variants in 8-cell human embryos, a potential approach for reducing human susceptibility to AD or other genetic diseases.

Clinical and molecular genetic analysis of a child with Schmid type metaphyseal chondrodysplasia / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical features and genotype of a child with Schmid type metaphyseal chondrodysplasia.@*METHODS@#Clinical data of the child and her parents was collected. The child was subjected to high-throughput sequencing, and candidate variant was verified by Sanger sequencing of her family members.@*RESULTS@#Whole exome sequencing revealed that the child has harbored a heterozygous c.1772G>A (p.C591Y) variant of the COL10A1 gene, which was not found in either of her parents. The variant was not found in the HGMD and ClinVar databases, and was rated as likely pathogenic based on the guidelines from the American College of Medical Genetics and Genomics (ACMG).@*CONCLUSION@#The heterozygous c.1772G>A (p.C591Y) variant of the COL10A1 gene probably underlay the Schmid type metaphyseal chondrodysplasia in this child. Genetic testing has facilitated the diagnosis and provided a basis for genetic counselling and prenatal diagnosis for this family. Above finding has also enriched the mutational spectrum of the COL10A1 gene.

Genetic analysis of a Chinese pedigree with Lesch-Nyhan syndrome / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic etiology for a Chinese pedigree affected with Lesch-Nyhan syndrome.@*METHODS@#Members of the pedigree who had visited the Genetic Counseling Clinic of Linyi People's Hospital on February 10, 2022 were selected as the study subjects. Clinical data and family history of the proband were collected, and trio-whole exome sequencing (trio-WES) was carried out for the proband and his parents. Candidate variants were verified by Sanger sequencing.@*RESULTS@#Trio-WES revealed that both the proband and his cousin brother had harbored a hemizygous c.385-1G>C variant in intron 4 of the HPRT1 gene, which was unreported previously. A heterozygous c.385-1G>C variant of the HPRT1 gene was also found in the proband's mother, grandmother, two aunts, and a female cousin, whilst all phenotypically normal males in his pedigree were found to have a wild type for the locus, which has conformed to an X-linked recessive inheritance.@*CONCLUSION@#The heterozygous c.385-1G>C variant of the HPRT1 gene probably underlay the Lesch-Nyhan syndrome in this pedigree.

Analysis of a case of Multiple pterygium syndrome due to a novel variant of CHRNG gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical characteristics and genetic etiology of a child with multiple pterygium syndrome (MPS).@*METHODS@#A child with MPS who was treated at the Orthopedics Department of Guangzhou Women and Children's Medical Center Affiliated to Guangzhou Medical University on August 19, 2020 was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples of the child and her parents were also collected. Whole exome sequencing (WES) was carried out for the child. Candidate variant was validated by Sanger sequencing of her parents and bioinformatic analysis.@*RESULTS@#The child, an 11-year-old female, had a complain of "scoliosis found 8 years before and aggravated with unequal shoulder height for 1 year". WES results revealed that she has carried a homozygous c.55+1G>C splice variant of the CHRNG gene, for which both of her parents were heterozygous carriers. By bioinformatic analysis, the c.55+1G>C variant has not been recorded by the CNKI, Wanfang data knowledge service platform and HGMG databases. Analysis with Multain online software suggested that the amino acid encoded by this site is highly conserved among various species. As predicted with the CRYP-SKIP online software, the probability of activation and skipping of the potential splice site in exon 1 caused by this variant is 0.30 and 0.70, respectively. The child was diagnosed with MPS.@*CONCLUSION@#The CHRNG gene c.55+1G>C variant probably underlay the MPS in this patient.

Genetic analysis of a patient with familial hypercholesterolemia due to variant of LDLR gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze variant of LDLR gene in a patient with familial hypercholesterolemia (FH) in order to provide a basis for the clinical diagnosis and genetic counseling.@*METHODS@#A patient who had visited the Reproductive Medicine Center of the First Affiliated Hospital of Anhui Medical University in June 2020 was selected as the study subject. Clinical data of the patient was collected. Whole exome sequencing (WES) was applied to the patient. Candidate variant was verified by Sanger sequencing. Conservation of the variant site was analyzed by searching the UCSC database.@*RESULTS@#The total cholesterol level of the patient was increased, especially low density lipoprotein cholesterol. A heterozygous c.2344A>T (p.Lys782*) variant was detected in the LDLR gene. Sanger sequencing confirmed that the variant was inherited from the father.@*CONCLUSION@#The heterozygous c.2344A>T (p.Lys782*) variant of the LDLR gene probably underlay the FH in this patient. Above finding has provided a basis for genetic counseling and prenatal diagnosis for this family.

Analysis of F12 gene variants and molecular mechanisms in patients with coagulation factor Ⅻ deficiency / 中华医学遗传学杂志

OBJECTIVE@#To analyze the sequence of the F12 gene and molecular mechanism for 20 patients with coagulation factor Ⅻ (FⅫ) deficiency.@*METHODS@#The patients were selected from the outpatient department of the Second Hospital of Shanxi Medical University from July 2020 to January 2022. The activity of coagulation factor Ⅷ (FⅧ:C), factor Ⅸ (FⅨ:C), factor Ⅺ (FⅪ:C) and factor Ⅻ (FⅫ:C) were determined by using a one-stage clotting assay. All exons and 5' and 3' UTR of the F12 gene were analyzed by Sanger sequencing to detect the potential variants. Bioinformatic software was used to predict the pathogenicity of the variants, conservation of amino acids, and protein models.@*RESULTS@#The FⅫ:C of the 20 patients has ranged from 0.07% to 20.10%, which was far below the reference values, whilst the other coagulation indexes were all normal. Sanger sequencing has identified genetic variants in 10 patients, including 4 with missense variants [c.820C>T (p.Arg274Cys), c.1561G>A (p.Glu521Lys), c.181T>C (p.Cys61Arg) and c.566.G>C (p.Cys189Ser)], 4 deletional variants c.303_304delCA(p.His101GlnfsX36), 1 insertional variant c.1093_1094insC (p.Lys365GlnfsX69) and 1 nonsense variant c.1763C>A (p.Ser588*). The remaining 10 patients only harbored the 46C/T variant. The heterozygous c.820C>T(p.Arg274Cys) missense variant in patient 1 and the homozygous c.1763C>A (p.Ser588*) nonsense variant in patient 2 were not included in the ClinVar and the Human Gene Mutation Database. Bioinformatic analysis predicted that both variants were pathogenic, and the corresponding amino acids are highly conserved. The protein prediction models suggested that the c.820C>T (p.Arg274Cys) variant may affect the stability of the secondary structure of FⅫ protein by disrupting the original hydrogen bonding force and truncating the side chain, leading to changes in the vital domain. c.1763C>A (p.Ser588*) may produce a truncated C-terminus which may alter the spatial conformation of the protein domain and affect the serine protease cleavage site, resulting in extremely reduced FⅫ:C.@*CONCLUSION@#Among individuals with low low FⅫ:C detected by one-stage clotting assay, 50% have harbored variants of the F12 gene, among which the c.820C>T and c.1763C>A were novel variants underlying the reduced coagulating factor FⅫ.

Clinical characteristics and genetic variant analysis of a child with Snijders Blok-Campeau syndrome / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical phenotype and genetic variant of a child with Snijders Blok-Campeau syndrome (SBCS).@*METHODS@#A child who was diagnosed with SBCS in June 2017 at Henan Children's Hospital was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples of the child and his parents were collected and the extraction of genomic DNA, which was subjected to trio-whole exome sequencing (trio-WES) and genome copy number variation (CNV) analysis. Candidate variant was verified by Sanger sequencing of his pedigree members.@*RESULTS@#The main clinical manifestations of the child have included language delay, intellectual impairment and motor development delay, which were accompanied with facial dysmorphisms (broad forehead, inverted triangular face, sparse eyebrows, widely spaced eyes, narrow palpebral fissures, broad nose bridge, midface hypoplasia, thin upper lip, pointed jaw, low-set ears and posteriorly rotated ears). Trio-WES and Sanger sequencing revealed that the child has harbored a heterozygous splicing variant of the CHD3 gene, namely c.4073-2A>G, for which both of his parents were of wild-type. No pathogenic variant was identified by CNV testing.@*CONCLUSION@#The c.4073-2A>G splicing variant of the CHD3 gene probably underlay the SBCS in this patient.

Genotype and Phenotype of α-Thalassemia Fusion Gene in Huadu District of Guangzhou, Guangdong Province of China / 中国实验血液学杂志

OBJECTIVE@#To explore the carrier rate, genotype and phenotype of α-thalassemia fusion gene in Huadu district of Guangzhou, Guangdong province of China, and provide data reference for the prevention and control of thalassemia.@*METHODS@#A total of 10 769 samples who were screened for thalassemia in Maternal and Child Health Hospital of Huadu District from July 2019 to November 2020 were analyzed retrospectively. Blood cell analysis and hemoglobin (Hb) electrophoresis were performed. Thalassemia genes were analyzed by gap-PCR and PCR-reverse dot blot hybridization (PCR-RDB).@*RESULTS@#A total of 9 cases with α-thalassemia fusion gene were detected in 10 769 samples (0.08%). There were 7 cases with fusion gene heterozygote, 1 case with compound of α-thalassemia fusion gene and Hb G-Honolulu, 1 case with compound of α-thalassemia fusion gene and Hb QS. The MCV results of 4 samples of blood cell analysis were within the reference range, the Hb A2 value of 1 case was decreased, and there were no other abnormalities found.@*CONCLUSION@#The α-thalassemia fusion gene is common in Huadu district of Guangzhou, and heterozygotes are more common, and current screening methods easily lead to misdiagnosis.

Clinical characteristics and genetic analysis of a patient with STISS syndrome due to variant of PSMD12 gene / 中华医学遗传学杂志

OBJECTIVE@#To investigate the clinical and genetic characteristics of a patient with STISS syndrome due to variant of PSMD12 gene.@*METHODS@#Clinical data and result of genetic testing of a patient who was admitted to Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine on October 4, 2020 were analyzed, together with a review of relevant literature.@*RESULTS@#The patient was found to harbor a heterozygous c.601C>T (p.Arg201*) nonsense variant of the PSMD12 gene, which was unreported previously. Clinically, the height of the patient has differed significantly from reported in the literature. An extremely rare case of STISS syndrome due to variant of the PSMD12 gene has been diagnosed.@*CONCLUSION@#Whether the severely short stature is part of the clinical spectrum for PSMD12 gene variants needs to be further explored, and the efficacy and safety of growth hormone therapy has yet to be determined.

A case of dilated cardiomyopathy caused by FHL2 gene variant and a literature review / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical phenotype and genetic features of a child with dilated cardiomyopathy (DCM).@*METHODS@#Clinical data of the child who had presented at the Zhengzhou Children's Hospital on April 28, 2020 was collected. Trio-whole exome sequencing (trio-WES) was carried out for the child and her parents, and candidate variants were validated by Sanger sequencing. "FHL2" was taken as the key word to retrieve related literature from January 1, 1997 to October 31, 2021 in the PubMed database and was also searched in the ClinVar database as a supplement to analyze the correlation between genetic variants and clinical features.@*RESULTS@#The patient was a 5-month-old female infant presented with left ventricular enlargement and reduced systolic function. A heterozygous missense variant c.391C>T (p.Arg131Cys) in FHL2 gene was identified through trio-WES. The same variant was not detected in either of her parents. A total of 10 patients with FHL2 gene variants have been reported in the literature, 6 of them had presented with DCM, 2 with hypertrophic cardiomyopathy (HCM), and 2 with sudden unexplained death (SUD). Phenotypic analysis revealed that patients with variants in the LIM 3 domain presented hypertrophic cardiomyopathy and those with variants of the LIM 0~2 and LIM 4 domains had mainly presented DCM. The c.391C>T (p.Arg131Cys) has been identified in a child with DCM, though it has not been validated among the patient's family members. Based on the guidelines of the American College of Medical Genetics and Genomics, the c.391C>T(p.Arg131Cys) variant was re-classified as likely pathogenic (PS2+PM2_Supporting+PP3+PP5).@*CONCLUSION@#The heterozygous missense variant of c.391C>T (p.Arg131Cys) in the FHL2 gene probably predisposed to the DCM in this child, which has highlighted the importance of WES in the clinical diagnosis and genetic counseling.

Analysis of OTC gene variants in four children with delayed onset Ornithine transcarbamylase deficiency / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical manifestation and genetic basis for four children with delayed onset Ornithine transcarbamylase deficiency (OTCD).@*METHODS@#Clinical data of four children with OTCD admitted to the Children's Hospital of the First Affiliated Hospital of Zhengzhou University from January 2020 to April 2021 were reviewed. Peripheral blood samples of the children and their parents were collected and subjected to whole exome sequencing (WES). Bioinformatic analysis and Sanger sequencing verification were carried out to verify the candidate variants. Impact of the candidate variants on the protein structure was also predicted.@*RESULTS@#The clinical manifestations of the four children included vomiting, convulsion and disturbance of consciousness. WES revealed that the child 1 was heterozygous for a c.421C>T (p.R141X) variant in exon 5, children 2 and 3 were hemizygous for a c.119G>A (p.R40H) variant in exon 2, and child 4 was hemizygous for a c.607T>A (p.S203T) variant in exon 5 of the OTC gene. Among these, the c.607T>A variant was unreported previously and predicted to be pathogenic (PM1+PM2_Supporting+PP3+PP4). Bioinformatic analysis has predicted that the variant may result in breakage of hydrogen bonds and alter the protein structure and function. Sanger sequencing confirmed that the variants in children 2 to 4 have derived from their mothers.@*CONCLUSION@#The pathogenic variants of the OTC gene probably underlay the delayed OTCD in 4 children. The discovery of the c.607T>A variant has enriched the mutational spectrum of the OTC gene.

Phenotypic and genetic analysis of a Chinese pedigree affected with Oral-facial-digital syndrome / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical phenotype and genetic basis for a Chinese pedigree affected with Oral-facial-digital syndrome type I (OFD1).@*METHODS@#A pedigree with OFD1 who presented at Hebei General Hospital on March 17, 2021 was selected as the subject. Clinical data of the child was collected. Trio-whole exome sequencing (trio-WES) was carried out for the proband and members of her pedigree, and candidate variant was verified by Sanger sequencing.@*RESULTS@#The proband has featured hypotelorism, broad nasal root, flat nasal tip, lobulated tongue, tongue neoplasia, camptodactyly of left fifth finger, syndactyly of right fourth and fifth fingers, and delayed intellectual and language development. Trio-WES revealed that the proband and her daughter, sister and mother have harbored a heterozygous c.224A>G (p.Asn75Ser) variant of the OFD1 gene. The same variant was not found among healthy members from her pedigree.@*CONCLUSION@#The c.224A>G (p.Asn75Ser) variant probably underlay the OFD1 in this pedigree. Above discovery has enriched the spectrum of OFD1 gene variants.

Analysis of genetic variant in a child with Aspartylglucosaminuria / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a child with Aspartylglucosaminuria (AGU).@*METHODS@#Clinical data of the patient was analyzed. The child was subjected to trio-whole exome sequencing (WES) and copy number variation sequencing (CNV-seq), and candidate variant was verified by Sanger sequencing.@*RESULTS@#The child was found to harbor homozygous c.319C>T (p.Arg107*) nonsense variant of the AGA gene, for which both of his parents were heterozygous carriers. No abnormality was found by CNV-seq analysis. The c.319C>T (p.Arg107*) variant was not found in population database, HGMD and other databases. Based on guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be pathogenic (PVS1+PM2+PP3).@*CONCLUSION@#The c.319C>T variant of the AGA gene probably underlay the autosomal recessive AGU in this child. Above finding has enabled genetic counseling and prenatal diagnosis for his parents.

A case of mental retardation caused by a frameshift variant of SYNGAP1 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a child with mental retardation.@*METHODS@#Whole exome sequencing was carried out for the child. Candidate variant was screened based on his clinical features and verified by Sanger sequencing.@*RESULTS@#The child was found to harbor a c.995_1002delAGACAAAA(p.Asp332AlafsTer84) frameshift variant in the SYNGAP1 gene. Bioinformatic analysis suggested it to be pathogenic. The same variant was not detected in either parent.@*CONCLUSION@#The c.995_1002delAGACAAAA(p.Asp332AlafsTer84) frameshift variant of the SYNGAP1 gene probably underlay the mental retardation in this child. Above finding has expanded the spectrum of SYNGAP1 gene variants and provided a basis for the diagnosis and treatment for this child.

Clinical and genetic analysis of a child with Schaaf-Yang syndrome / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical characteristics and genetic etiology of a child with Schaaf-Yang syndrome (SYS).@*METHODS@#Peripheral blood samples of the child and his parents were collected and subjected to whole exome sequencing. Sanger sequencing was used for family constellation verification, and bioinformatic analysis was performed for the candidate variant.@*RESULTS@#The child, a 1-year-and-9-month-old boy, had clinical manifestations of retarded growth, small penis, and unusual facies. Genetic testing revealed that the child has harbored a novel heterozygous variant of c.3078dupG (p.Leu1027Valfs*28) of the MAGEL2 gene. Sanger sequencing showed that neither parent of the child carried the same variant. The c.3078dupG(p.Leu1027Valfs*28) variant of the MAGEL2 gene has not been included in the databases of ESP, 1000 Genomes and ExAC. According to the Standards and Guidelines for the Interpretation of Sequence Variants of the American College of Medical Genetics and Genomics (ACMG), the variant was judged to be pathogenic.@*CONCLUSION@#The c.3078dupG (p.Leu1027Valfs*28) variant of the MAGEL2 gene probably underlay the SYS in this child, which has further expanded the spectrum of the MAGEL2 gene variants.

Analysis of a child with autosomal dominant mental retardation type 40 due to variant of CHAMP1 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical and genetic features of a child with autosomal dominant mental retardation type 40 (MRD40) due to variant of the CHAMP1 gene.@*METHODS@#Clinical characteristics of the child were analyzed. Genetic testing was carried out by low-depth high-throughput and whole genome copy number variant sequencing (CNV-seq) and whole exome sequencing (WES). A literature review was also carried out for the clinical phenotype and genetic characteristics of patients with MRD40 due to CHAMP1 gene variants.@*RESULTS@#The child, a 11-month-old girl, has presented with intellectual and motor developmental delay. CNV-seq revealed no definite pathogenic variants. WES has detected the presence of a heterozygous c.1908C>G (p.Y636*) variant in the CHAMP1 gene, which was carried by neither parent and predicted to be pathogenic. Literature review has identified 33 additional children from 12 previous reports. All children had presented with developmental delay and mental retardation, and most had dystonia (94.1%), delayed speech and/or walking (85.2%, 82.4%) and ocular abnormalities (79.4%). In total 26 variants of the CHAMP1 gene were detected, with all nonsense variants being of loss-of-function type, located in exon 3, and de novo in origin.@*CONCLUSION@#The heterozygous c.1908C>G (p.Y636*) variant of the CHAMP1 gene probably underlay the WRD40 in this child. Genetic testing should be considered for children featuring global developmental delay, mental retardation, hypertonia and facial dysmorphism.

Analysis of A Pedigree with Hereditary Coagulation Factor Ⅻ Deficiency Caused by Compound Heterozygous Mutations / 中国实验血液学杂志

OBJECTIVE@#To analysis clinical phenotype and potential genetic cause of a family affected with hereditary coagulation factor Ⅻ deficiency.@*METHODS@#The prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), D-Dimer (D-D), coagulation factor Ⅻ activity (FⅫ:C) and coagulation factor Ⅻ antigen (FⅫ:Ag) were determined for phenotype diagnosis of the proband and his family members(3 generations and 5 people). Targeted capture and whole exome sequencing were performed in peripheral blood sample of the proband. Possible disease-causing mutations of F12 gene were obtained and further confirmed by Sanger sequencing. The corresponding mutation sites of the family members were analyzed afterwards. The online bioinformatics software AutoPVS1 and Mutation Taster was used to predict the effects of mutation sites on protein function.@*RESULTS@#The APTT of the proband was significantly prolonged, reaching 180.9s. FⅫ:C and FⅫ:Ag of the proband was significantly reduced to 0.8% and 4.17%, respectively. The results of whole exome sequencing displayed that there were compound heterozygous mutations in F12 gene of the proband, including the c.1261G＞T heterozygous nonsense mutation in exon 11 (causing p.Glu421*) and the c.251dupG heterozygous frameshift mutation in exon 4 (causing p.Trp85Metfs*53). Both mutations are loss of function mutations with very strong pathogenicity, leading to premature termination of the protein. AutoPVS1 and Mutation Taster software predicted both mutations as pathogenic mutations. The results of Sanger sequencing revealed that c.1261G＞T heterozygous mutation of the proband was inherited from his mother, for which his brother and his daughter were c.1261G＞T heterozygous carriers. Genotype-phenotype cosegregation was observed in this family.@*CONCLUSION@#The c.1261G＞T heterozygous nonsense mutation in exon 11 and the c.251dupG heterozygous frameshift mutation in exon 4 of the F12 gene probably account for coagulation factor Ⅻ deficiency in this family. This study reports two novel pathogenic F12 mutations for the first time worldwide.

Clinical Diagnosis and Prenatal Screening of Hb Lepore-BW Associated with IVS-II-654 Heterozygous Mutation / 中国实验血液学杂志

OBJECTIVE@#To identify one case of rare Hb Lepore-BW associated with IVS-II-654 heterozygous mutation in Sichuan area.@*METHODS@#The blood routine examination and hemoglobin electrophoresis methods were used to analyze the blood routine parameters, HbA2 and HbF in the samples of peripheral blood in proband and his parents, as well as the cord blood of pregnant woman. The detection of thalassemia gene and Sanger sequencing methods were used to detect the hemoglobin mutations.@*RESULTS@#The result showed that the Hb Lepore-BW heterozygous mutation was detected in the father of the proband, while a rare Hb Lepore-BW with IVS-II-654 heterozygous mutation was detected in the proband, as well as his mother and cord blood were both detected as IVS-II-654 heterozygous mutation.@*CONCLUSION@#The study identified a rare Hb Lepore-BW with IVS-II-654 heterozygous mutation, which was characterized by intermediate β-thalassemia. It is necessary to hemoglobin electrophoresis combined with routine blood testing in prenatal screening.

Genetic Mutation Characteristics of Glucose-6-Phosphate Dehydrogenase Deficiency Patients in Wuhan / 中国实验血液学杂志

OBJECTIVE@#To explore the genotype mutation characteristics of patients with glucose-6-phosphate dehydrogenase(G6PD) deficiency in Wuhan.@*METHODS@#A total of 1 321 neonates with positive screening and outpatients were received G6PD mutation detection, 12 kinds of common G6PD mutation in Chinese people was detected by using multicolor melting curve analysis (MMCA) method, for those with negative results, the enzyme activity and clinical information were analyzed, sequencing was recommended after informed consent when it is necessary.@*RESULTS@#Among 1321 patients, a total of 768 mutations were detected out, with a detection rate of 58.1%. A total of 18 types of G6PD genotypes were identified, including c.1388G>A, c.1376G>T, c.95G>A, c.1024C>T, c.871G>A, c.392G>T, c.487G>A, c.1360C>T, c.1004C>A, c.517T>C, c.592C>T, c.94C>G, c.152C>T, c.320A>G, c.1028A>G, c.1316G>A, c.1327G>C and c.1376G>C, including 683 male hemizygotes, 3 female homozygotes, 80 female heterozygotes and 2 female compound heterozygous.@*CONCLUSION@#A total of 18 types of G6PD mutations are identified in the reaserch, and c.94C>G, c.1028A>G and c.1327G>C are first reported in Chinese population. The most common G6PD mutation types in Wuhan are c.1388G>A, c.1376G>T, c.95G>A.

Study on Thalassemia in Han Population in Sanya of Hainan Province / 中国实验血液学杂志

OBJECTIVE@#To study the distribution characteristics of thalassemia genotype in Han Population in Sanya of Hainan Province.@*METHODS@#Gap PCR and reverse dot hybridization were used to detect and analyze the thalassemia gene in 572 suspected thalassemia carriers of Han Population in Sanya.@*RESULTS@#Among the 572 Han Population in Sanya, 271 cases of thalassemia gene abnormality were detected, among which 161 cases were founded to be carriers of α-thalassemia gene. A total of 9 genotypes were detected, in the following order of the detection rate was －－SEA/αα，－α3.7/αα，－α4.2/αα，－－SEA/－α3.7，－－SEA/－α4.2，－α4.2/－α4.2，－α3.7/－α4.2，－α3.7/－α3.7，－－SEA/－－SEA. Among them, the deletion type (－－SEA/αα) in southeast Asia was the most common, accounting for 66 cases. 99 cases of β-thalassemia were detected, there were 7 genotypes, all of which were heterozygous. The order of the detection rate was CD41-42/βN, IVS-II-654/βN, CD17/βN, CD71-72/βN, -28/βN, －29/βN, CD27-28/βN. Among them, CD41-42/βN was the most common, accounting for 51 cases. In addition, 11 cases of combined α and β thalassemia were detected. Five kinds of genotypes were checked out, the order of detection rate was －α3.7/αα composite CD41-42/βN, －－SEA/αα composite IVS-II-654/βN, －α4.2/－α4.2 composite CD41-42/βN, －α4.2/αα composite －29/βN , －－SEA/ －α4.2 composite CD41-42/βN.@*CONCLUSION@#Han Population in Sanya of Hainan Province is a high-risk population of thalassemia, the genotype characteristics are different from other areas with high incidence of thalassemia in China. The main type of α-thalassemia is the deficiency mutation of southeast Asia, while CD41-42 heterozygous mutation is the main type of β-thalassemia.