[Analysis of gene variant in a Chinese pedigree with preaxial polydactyly].

OBJECTIVE: To analyze the pathogenic variant of preaxial polydactyly in a Chinese Han pedigree and identify the cause of polydactyly. METHODS: The peripheral blood DNA of the proband and her parents was extracted. The polydactyly-related genes were detected by trio whole exome sequencing, and the suspected pathogenic gene was screened out. Sanger sequencing was applied to other members of the pedigree. RESULTS: The results of gene sequencing showed that the LMBR1 gene had a heterozygous variant of c.423+4909(IVS5)C>T in 6 patients of the pedigree. The same variant was not detected in family members with normal phenotype. Based on the ACMG guidelines, c.423+4909(IVS5)C>T of the LMBR1 gene was predicted to be pathogenic (PM1+PM2+PP1-S(PS)+PP4+PP5). CONCLUSION: The heterozygous C>T variant at position 4909 of intron 5 of the LMBR1 gene probably underlies the disease in this pedigree.

[Identification of a novel SOD1 variant in a Chinese patient with amyotrophic lateral sclerosis].

OBJECTIVE: To explore the genetic basis for a Chinese patient with amyotrophic lateral sclerosis (ALS). METHODS: Peripheral blood samples were collected from the patient and his parents for the extraction of genomic DNA. Genetic variant was identified by whole exome sequencing. Candidate variant was verified by Sanger sequencing of his parents and healthy controls. RESULTS: The patient was found to harbor a heterozygous c.420C>G (p.Asn140Lys) variant of the SOD1 gene. The same variant was not detected in his parents and 100 healthy controls. The variant has not been included in HGMD, dbSNP and other databases. CONCLUSION: The c.420C>G variant of the SOD1 gene may underlie the ALS in this patient. Above finding has enriched the spectrum of SOD1 gene variants.