5. Identification of a pathogenic variant in a family with megaconial congenital muscular dystrophy
Main Article Content
Abstract
Megaconial congenital muscular dystrophy (MDCMC) is a rare autosomal recessive disorder characterized by early-onset muscle weakness, hypotonia, growth delay, ichthyosis, dilated cardiomyopathy, elevated serum creatine kinase level, and distinctive histological features such as enlarged peripheral mitochondria in skeletal muscle fibers. This condition is caused by pathogenic variants in both copies of the CHKB gene. In this study, a pathogenic variant, CHKB: c.598delC p.(Q200Rfs*11), was identified in the homozygous state in two siblings from a family affected by congenital muscular dystrophy diagnosed after birth. Based on their clinical features and genetic analysis, both children were diagnosed with MDCMC. Sanger sequencing revealed that their parents carried the pathogenic variant in the heterozygous form. Following genetic counseling, the parents opted for in vitro fertilization and preimplantation genetic diagnosis. The results showed that four out of seven embryos had a heterozygous genotype. One of these 4 embryos was implanted in the mother and a healthy baby boy was born. Thus, genetic testing not only supported a definitive diagnosis for the patient but also provided the basis for genetic counseling for the family. For couples carrying the disease gene, in vitro fertilization and preimplantation genetic diagnosis will ensue in healthy children.
Article Details
Keywords
Megaconial congenital muscular dystrophy, CHKB gene, Vietnamese, preimplantation genetic testing
References
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