[Application of low-depth whole genome sequencing for copy number variation analysis in children with disorders of sex development].

OBJECTIVE

To assess the value of copy number variation sequencing (CNV-seq) for the diagnosis of children with disorders of sex development (DSD).

METHODS

Five children with DSD who presented at the First Affiliated Hospital of Zhengzhou University from October 2019 to October 2020 were enrolled. In addition to chromosomal karyotyping, whole exome sequencing (WES), SRY gene testing, and CNV-seq were also carried out.

RESULTS

Child 1 and 2 had a social gender of female, whilst their karyotypes were both 46,XY. No pathogenic variant was identified by WES. The results of CNV-seq were 46,XY,+Y (1.4) and 46,XY,-Y (0.75), respectively. The remaining three children have all carried an abnormal chromosome Y. Based on the results of CNV-seq, their karyotypes were respectively verified as 45,X[60]/46,X,del(Y)(q11.221)[40], 45,X,16qh+[76]/46,X,del(Y)(q11.222),16qh+[24], and 45,X[75]/46,XY[25].

CONCLUSION

CNV-seq may be used to verify the CNVs on the Y chromosome among children with DSD and identify the abnormal chromosome in those with 45,X/46,XY. Above results have provided a basis for the clinical diagnosis and treatment of such children.