Case Report: unmasking pseudo-homozygosity in CYP21A2: intergenerational gene conversion expansion and the necessity of multimodal genetic testing
CYP21A2 gene mutations causing Congenital Adrenal Hyperplasia (CAH) exhibit high allelic complexity. Rare meiotic events, such as de novo expansion of deletion boundaries, can obscure true genotypes, leading to ‘pseudo-homozygosity’ and diagnostic pitfalls. This study characterizes a rare intergenerational expansion of...