46, XY,t(1;2;12;6;16)(q42;q23;q22;q13;q13) REPORT OF A CASE WITH SEX DIFFERENTIATION DISORDER (DSD) WITH COMPLEX CHROMOSOMAL REARRANGEMENT

Abstract

In this study, we present a case of a 7-month-and-26-day-old patient with a novel karyotype associated with a 46,XY disorder of sexual development. This complex chromosomal rearrangements, described as 46,XY,t(1;2;12;6;16)(q42;q23;q22;q13;q13), was confirmed by FISH analysis and has not been previously reported in the literature. The patient exhibited ambiguous genitalia and faced urinary obstruction. No pathogenic variants were detected in genes associated with disorders of sex development in the Next-Generation Sequencing (panel, suggesting that structural rearrangements may disrupt genes critical for sexual and neurological development. Laparoscopic-assisted urogenital mobilisation successfully improved urinary function and genital appearance. This case demonstrates that the pathogenesis of disorders of sex development may involve structural chromosomal abnormalities in addition to gene-level mutations and highlights the importance of genomic rearrangements in disorders of sexual development. The findings emphasise the need for a multidisciplinary approach to the diagnosis and management of complex cases of disorders of sex development. Chromosomal abnormalities should be considered even in the presence of normal sex development genes. This rare karyotype provides new insights into the genetic basis of disorders of sex development, as similar cases have not been documented. We believe that reporting such unique cases will contribute to the understanding of the molecular mechanisms of disorders of sex development and the development of clinical strategies. In summary, we emphasize that structural chromosomal alterations can contribute to disorders of sex development independently of gene mutations and the value of genetic, clinical, and surgical collaboration in patient evaluation. This case expands knowledge of the etiology of disorders of sex development and supports further research on structural genomic alterations.

Keywords

• DSD
• ambiguous genitalia
• complex chromosomal rearrangement.

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