Open AccessTwo Cases of Facioscapulohumeral Muscular Dystrophy 2 in Korea
Author(s) -
Jung Hwan Lee,
Hyung Jun Park,
Moon-Woo Seong,
Sung Sup Park,
Young Chul Choi
Publication year - 2021
Publication title -
yonsei medical journal/yonsei medical journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.702
H-Index - 63
eISSN - 1976-2437
pISSN - 0513-5796
DOI - 10.3349/ymj.2021.62.1.95
Subject(s) - facioscapulohumeral muscular dystrophy , subtelomere , medicine , muscular dystrophy , pectoral girdle , genetics , chromosome , haploinsufficiency , gene , anatomy , biology , phenotype
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant muscular disorder characterized by weakness of facial, shoulder, abdominal, hip girdle, humeral, and anterior distal leg muscles, with descending progression from the face to the legs in an asymmetric pattern. In about 5% of patients with FSHD, no D4Z4 repeat contraction on chromosome 4q35 is observed; this disease entity is called FSHD2. FSHD2 is characterized by DNA hypomethylation on the 4q-subtelomeric macrosatellite repeat array D4Z4. In Korea, there have been no previous reports of FSHD2. We report the first two cases of FSHD2 in Korea, carrying c.3801delG and c.1580C>T mutations in the SMCHD1 gene, respectively. For rapid and accurate diagnosis of FSHD2, genetic analysis of the D4Z4 haplotype and methylation with next-generation sequencing are required.