OBJECTIVE: To explore the genetic basis for a child featuring complex cortical dysplasia and other brain malformations (CDCBM3). METHODS: Genomic DNA was extracted from peripheral blood samples from the patient and his parents. Whole exome sequencing (WES) was carried out for the family trio. Suspected variant was verified by Sanger sequencing. RESULTS: The proband, a 1-year-and-2-month old Chinese boy, had presented with motor developmental delay, lissencephaly, severe cognitive impairments, absent speech and congenital laryngomalacia. WES revealed that he has harbored a heterozygous missense variant of the KIF2A gene, namely NM_001098511.2: c.952G>A, p.Gly318Arg (GRCh37/hg19). The highly conserved residue is located around the ATP nucleotide-binding pocket in the kinesin motor domain (PM1). The variant was not found in the Genome Aggregation Database and the 1000 Genomes Project (PM2), and was predicted to be deleterious on the gene product by multiple in silico prediction tools (PP3). This variant was unreported previously and was de novo in origin (PS2). Based on the ACMG guidelines, it was categorized as likely pathogenic (PS2+PM1+PM2+PP3). Furthermore, the congenital laryngomalacia found in our patient was absent in previously reported CDCBM3 cases. CONCLUSION The novel variant of the KIF2A gene probably underlay the disorders in the proband. Above finding has expanded the phenotypic and mutational spectrum of CDCBM3.
Asians/genetics* ; Brain ; China ; Humans ; Infant ; Kinesins/genetics* ; Male ; Malformations of Cortical Development/genetics* ; Whole Exome Sequencing

OBJECTIVE: To detect the genetic variant of a child with cleidocranial dysplasia (CCD) and to find out the causation of the illness. METHODS: Gene variant was identified by the second generation targeted sequencing and Sanger sequencing. RESULTS: The gene sequencing revealed that the RUNX2 gene had c.196C>T(p.Glu66*) nonsense variant, which was predicted to be a pathogenic variant according to the ACMG guidelines(PVS1+PS2). CONCLUSION The variant of c.196C > T in the RUNX2 gene may be the cause of the child with CCD, and the novel variant enriches the RUNX2 gene variant spectrum.
Asians/genetics* ; Child ; China ; Cleidocranial Dysplasia/genetics* ; Core Binding Factor Alpha 1 Subunit/genetics* ; Humans ; Mutation

OBJECTIVE: To explore the genotype-phenotype correlation of a case with GM1-gangliosidosis caused by compound heterogenic variants in GLB1. METHODS: Genomic DNA was extracted from peripheral blood samples from the patient and her parents. Trio-based whole-exome sequencing (WES) was performed for the family and suspected mutation was verified by Sanger sequencing. RESULTS: The proband, a 2-year-3-month old Chinese girl, presented with psychomotor deterioration, absent speech, intellectual disabilities and behavior problem. Trio-based WES has identified compound heterozygosity for 2 variants in the GLB1 gene: NM_000404.2:c.1343A>T, p.Asp448Val and c.1064A>C, p.Gln355Pro (GRCh37/hg19),which was inherited from the mother and father, respectively. Homozygous or compound heterozygous pathogenic variants in GLB1, encoding β-galactosidase, are responsible for GM1-gangliosidosis,an autosomal recessive lysosomal storage disorder characterized by variable degrees of neurodegeneration and skeletal abnormalities. The p.Asp448Val variant has been classified as pathogenic for GM1 gangliosidosis in medical literatures for the reason that functional studies demonstrated that expression of the p.Asp448Val variant in COS-1 cells resulted in no detectable β-galactosidase activity compared to wild type GLB1. The p.Gln355Pro variant has not been reported in literatures or database. The variant is highly conserved residue (PM1), and was not found in either the Genome Aggregation Database or the 1000 Genomes Project (PM2) and was predicted to have a deleterious effect on the gene product by multiple in silico prediction tools (PP3). Next, the β-galactosidase activity of the patient's peripheral blood leukocytes was determined by fluorescent method. The result was 0.0 nmol/mg. It showed that the p.Gln355Pro variant also resulted in loss of β-galactosidase activity, thus the variant was classified into clinical pathogenic variant. CONCLUSION Our study expands the mutational spectrum of the GLB1 gene and provides genetic counseling for the family.
Asians/genetics* ; China ; Female ; G(M1) Ganglioside ; Gangliosidosis, GM1/genetics* ; Humans ; Mutation ; beta-Galactosidase/genetics*

OBJECTIVES: To study the characteristics of UGT1A1 gene mutations in Dong neonates in Sanjiang County of Liuzhou and its association with the pathogenesis of hyperbilirubinemia in Dong neonates. METHODS: A prospective analysis was performed on 84 neonates who were diagnosed with unexplained hyperbilirubinemia in the Department of Neonatology, Sanjiang County People's Hospital, from January 2021 to January 2022. Sixty healthy neonates born during the same period were enrolled as the control group. Peripheral blood genomic DNA was extracted for both groups, and UGT1A1 exon 1 was amplified by PCR and sequenced. RESULTS: In the case group, 33 neonates were found to have G71R missense mutation, with a mutation rate of 39%. The case group had a significantly higher frequency of A allele than the healthy control group (21% vs 10%, P<0.05). The risk of hyperbilirubinemia in Dong neonates carrying G71R missense mutation was 2.588 times as high as that in healthy neonates carrying wild-type UGT1A1 gene (P<0.05). Hardy-Weinberg equilibrium testing showed that the UGT1A1 G71R locus was in genetic equilibrium in both groups (P>0.05). CONCLUSIONS UGT1A1 G71R mutation is a high-frequency gene mutation type in Dong neonates in Sanjiang County, and G71R missense mutation is associated with hyperbilirubinemia in Dong neonates.
Asians/genetics* ; China ; Exons ; Glucuronosyltransferase/genetics* ; Humans ; Hyperbilirubinemia, Neonatal/genetics* ; Infant, Newborn ; Mutation

Objective: To screen and analyze the mutations of MITF gene in two children of type Ⅱ Waardenburg syndrome (WS2) from different families in Yunnan,China,and to explore the possible molecular pathogenesis. Methods: With informed consent, medical history collection, physical examinations, audiological evaluation, and high resolution computer tomography (HRCT) scan of temporal bone were performed on the two WS2 probands and their family members. Genomic DNA was extracted from peripheral blood of all individuals. The coding regions including all exons, part of introns and promoters of MITF, PAX3, SOX10, SNAI2, END3, ENDRB, and KITLG genes were sequenced by high-throughput sequencing. According to the results of high-throughput sequencing, pathogenic mutations detected in the probands and their parents were verified by Sanger sequencing. Results: The proband 1 carried c.641_643delGAA mutation in the 7th exon of MITF gene, which was a frame-shift mutation resulting in an amino acid change of p.214delR. It was a de novo mutation as the parents of proband 1 showed no variation on this site. The proband 2 carried heterozygous loss of the large fragment ranging from exon 1 to exon 9 of MITF gene, which defected the function of MITF protein. Conclusion: Genetic examinations provide important evidence for diagnosis of Waardenburg syndrome. Heterozygous mutation c.641_643delGAA and heterozygous loss of the large fragment ranging from exon 1 to exon 9 of MITF gene might be the molecular pathogenesis of the two WS2 probands in this study.
Asians/genetics* ; Child ; China ; Humans ; Mutation ; Pedigree ; SOXE Transcription Factors/genetics* ; Waardenburg Syndrome/genetics*

OBJECTIVE: To explore the genetic basis for a Chinese patient with retinitis pigmentosa (RP). METHODS: Whole exome sequencing (WES) was carried out to screen potential variant in the proband. Candidate variants were determined by taking consideration of clinical phenotype. Sanger sequencing was used to verify the variant in the proband and his parents. RESULTS: The proband was found to harbor compound heterozygous variants of c.8G>A (p.Cys3Tyr) and c.958_959insA (p.Arg320Glnfs*29) in the C2ORF71 gene, which has derived from his father and mother, respectively. Both variants were unreported previously. Based on the ACMG guidelines, they were predicted to be likely pathogenic and pathogenic, respectively. CONCLUSION The novel compound heterozygous variants of the C2ORF71 gene probably underlay the pathogenesis of RP in the proband. Above finding has enriched the spectrum of C2ORF71 gene mutations and facilitated genetic counseling for the family.
Asians/genetics* ; China ; Humans ; Mutation ; Pedigree ; Retinitis Pigmentosa/genetics* ; Whole Exome Sequencing

OBJECTIVE: To analyze the clinical features and variants of ABCD1 gene in a Chinese pedigree affected with X-linked adrenoleukodystrophy. METHODS: Clinical data of the proband were collected and analyzed. Potential variant of the ABCD1 gene were analyzed by PCR and Sanger sequencing of the proband, his parents and 100 unrelated healthy individuals. RESULTS: The prominent features of the proband included cerebellar and brainstem lesions, along with increased serum level of very-long chain fatty acids. He was found to harbor a hemizygous c.1509delG (p.L504Sfs*54) variant of the ABCD1 gene, for which his mother was heterozygous. The same variant was not detected in his father and 100 healthy controls. CONCLUSION X-linked adrenoleukodystrophy has a variety of clinical manifestations. Discovery of the c.1509delG (p.L504Sfs*54), as a novel pathogenic variant of the ABCD1 gene, has enabled diagnosis and genetic counseling for this pedigree.
Adrenoleukodystrophy/genetics* ; Asians/genetics* ; China ; Female ; Genetic Testing ; Humans ; Male ; Mutation ; Pedigree

OBJECTIVE: To study the polymorphism of human platelet antigen (HPA) system 10 among ethnic Han Chinese from Shandong, China so as to supplement the data of platelet donor bank in the region. METHODS: Peripheral blood samples of platelet donors from the region were genotyped for HPA-10 alleles by PCR-sequence specific primer (PCR-SSP) and direct sequencing. RESULTS: Among 1401 donors, a rare heterozygote carrier of HPA-10w (a+b+) was identified, which gave an allelic frequency of approximately 0.035%. CONCLUSION The detection of rare HPA-10bw antigen allele among ethnic Han Chinese from Shandong is useful for the diagnosis and prevention of neonatal alloimmune thrombocytopenia and post-transfusion purpura in the region.
Alleles ; Antigens, Human Platelet/genetics* ; Asians/genetics* ; Gene Frequency ; Genotype ; Humans ; Infant, Newborn ; Polymorphism, Genetic

OBJECTIVE: In this study, we used genome-wide association study (GWAS) data to explore whether WNT pathway genes were associated with non-syndromic oral clefts (NSOC) considering gene-gene interaction and gene-environment interaction. METHODS: We conducted the analysis using 806 non-syndromic cleft lip with or without cleft palate (NSCL/P) case-parent trios and 202 non-syndromic cleft palate (NSCP) case-parent trios among Chinese populations selected from an international consortium established for a GWAS of non-syndromic oral clefts. Genotype data and maternal environmental exposures were collected through DNA samples and questionnaires. Conditional Logistic regression models were adopted to explore gene-gene interaction and gene-environment in teraction using trio package in R software. The threshold of significance level was set as 3.47×10^-4 using Bonferroni correction. RESULTS: A total of 144 single nucleotide polymorphisms (SNPs) in seven genes passed the quality control process in NSCL/P trios and NSCP trios, respectively. Totally six pairs of SNPs interactions showed statistically significant SNP-SNP interaction (P < 3.47×10^-4) after Bonferroni correction, which were rs7618735 (WNT5A) and rs10848543 (WNT5B), rs631948 (WNT11) and rs556874 (WNT5A), and rs631948 (WNT11) and rs472631 (WNT5A) among NSCL/P trios; rs589149 (WNT11) and rs4765834 (WNT5B), rs1402704 (WNT11) and rs358792 (WNT5A), and rs1402704 (WNT11) and rs358793 (WNT5A) among NSCP trios, respectively. In addition, no significant result was found for gene-environment interaction analysis in both of the NSCL/P trios and NSCP trios. CONCLUSION Though this study failed to detect significant association based on gene-environment interactions of seven WNT pathway genes and the risk of NSOC, WNT pathway genes may influence the risk of NSOC through potential gene-gene interaction.
Asians/genetics* ; Cleft Lip/genetics* ; Cleft Palate/genetics* ; Genome-Wide Association Study ; Humans ; Wnt Signaling Pathway/genetics*

OBJECTIVE: To explore the clinical features and genetic basis for a Chinese pedigree diagnosed with congenital glycosylation disease (CGD). METHODS: Clinical manifestations of two brothers were analyzed. Whole exome sequencing was carried out for the sib pair. Suspected variants were verified by Sanger sequencing. RESULTS: Both the proband and her younger brother were found to carry compound heterozygous variants of the PMM2 gene, which included a known pathogenic mutation of c.395T>C (p.I132T) and a previously unreported c.448-1(delAG) in the 5' end of exon 6 of the gene. CONCLUSION The compound heterozygous variants of the PMM2 gene probably underlay the CGD in the sib pair.
Asians/genetics* ; China ; Female ; Glycosylation ; Humans ; Male ; Mutation ; Pedigree ; Whole Exome Sequencing