Clinical features, gene mutation and genetic counseling in Rett syndrome patients / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the mutations in methyl-CpG-binding protein 2 gene (MECP2 gene) from typical sporadic Rett syndrome patients,explore the correlations between their genotype and phenotype,assist in genetic counseling.Methods Genomic DNA was extracted from peripheral blood leukocytes from 2 patients and their parents using standard protocols.Polymerase chain reaction and direct sequencing were performed using specific primers from 4 exons in MECP2 gene.Results No mutations were found in exon 1,2,3.Two different heterozygous missense mutations in exon 4 within MECP2 gene were identified from 2 patients.Their nuclear acid changes werec.C473T and c.C397T,leading to amino acid change accordinglyp.T158M and p.R133C.There were no same mutations from their parents.Phenotype of patient with c.C397T was milder than patient with c.C473T.Conclusions Most of typical Rett syndrome patients had mutations in MECP2 gene.Gene test should be performed.Their biological parents should be detected accordingly if the patient had positive found to support genetic counseling.