SNP Shot: Genomic Insights

Denys-Drash syndrome is a disorder impacting both the kidneys and the reproductive organs.

A hallmark of Denys-Drash syndrome is kidney disease that manifests very early in life. Individuals with this syndrome develop diffuse glomerulosclerosis, a condition where scar tissue develops within the glomeruli of the kidneys. These glomeruli are crucial blood vessels responsible for filtering waste products. This scarring typically progresses to kidney failure during childhood. Furthermore, individuals with Denys-Drash syndrome have a high (approximately 90%) likelihood of developing Wilms tumor, an uncommon type of kidney cancer. They may experience multiple tumors in one or both kidneys.

Despite possessing a standard male chromosome configuration (46,XY), males with Denys-Drash syndrome exhibit gonadal dysgenesis. This results in ambiguous genitalia, where the external reproductive organs don't clearly appear male or female, or they may appear entirely female. Their testes are typically undescended, meaning they are abnormally positioned outside the scrotum, in the pelvis, abdomen, or groin. Consequently, males with Denys-Drash syndrome are usually infertile.

Females affected by Denys-Drash syndrome generally present with normal genitalia and only exhibit the kidney-related aspects of the condition. Due to this incomplete presentation, these females are often diagnosed with isolated nephrotic syndrome rather than Denys-Drash syndrome.

Inheritance:

Denys-Drash syndrome follows an autosomal dominant inheritance pattern. This means that inheriting just one copy of the mutated gene in each cell is enough to cause the syndrome.