Incidental finding of a exons 48-55 deletion during prenatal diagnosis.

BACKGROUND

genetic variants cause a spectrum of phenotypes, from severe progressive proximal muscle weakness and degeneration leading to wheelchair dependence and death from cardiac and/or respiratory failure to very mild muscular phenotypes; very rarely, cases are completely asymptomatic. Few cases have been reported in males carrying deletions who are asymptomatic.

METHODS

Family clinical information was collected from the patients. A single nucleotide polymorphism array (SNP-array) was used to detect abnormalities in prenatal diagnosis, and multiplex ligation-dependent probe amplification (MLPA) and long-read sequencing (LRS) were used to confirm the detected variant.

RESULTS

We incidentally identified exons 48-55 deletion using SNP-array in prenatal diagnosis; the variant was confirmed using MLPA and LRS, and the fragment size and precise locations of breakpoints were determined. The variant was precisely located at genomic position chrX:31640088-31945085, spanning from intron 47 to intron 56 in . Serum biochemical indicators were normal in the male with the deletion.

CONCLUSION

Our study is the first to report a exons 48-55 deletion in prenatal diagnosis. The phenotypes of variants are diverse, and this study suggests that prediction of clinical severity based solely on molecular findings should be interpreted with caution.