Cytogenetic and molecular genetic analysis of Klinefelter syndrome in a fetus of Duchenne muscular dystrophy family / 中华围产医学杂志

ABSTRACT

A 44-year-old pregnant woman (G5P3) who had delivered two children with DMD was admitted and underwent prenatal diagnosis at Peking Union Medical College Hospital in 2019. (1) The karyotype of the fetus in 2019 was 47,XXY. The fluorescence in situ hybridization (FISH) result showed a nucish(CSPX×2, CSPY×1)[100] and multiplex ligation-dependent probe amplification (MLPA) suggested sex chromosome abnormality. Based on the above results, the fetus was diagnosed with Klinefelter syndrome. Fetal short tandem repeat (STR) linkage analysis and Sanger sequencing indicated a heterozygous mutation of c.9543delG(p.Trp3181CysfsTer2). (2) Sanger sequencing of the proband found a novel frameshift mutation of c.9543delG(p.Trp3181CysfsTer2 ) in exon 65 of the DMD gene. (3) The male fetus performing prenatal diagnosis in 2008 was found to have the same maternal gene markers as the proband with the same genotype. While the genotype of the fetus in 2009 obtained a different maternal gene marker from the proband and did not detect the same DMD gene mutation. This fetus was delivered at full term and was good during follow-up. (4) The elder brother and cousin of the proband had the same frameshift mutation in exon 65 of the DMD gene as the proband. The mother of the proband was a heterozygous carrier of the mutation.