[The frequency of X-linked mental retardation]

Area of Science:

• Pediatrics
• Genetics
• Neurodevelopmental Disorders

Context:

• Investigated the prevalence and characteristics of mental retardation in children.
• Examined a cohort of 600 children aged 5-9 years with mental retardation.
• Analyzed the boy-to-girl ratio (B:G) across different etiological categories.

Purpose:

• To determine the prevalence of mental retardation in children.
• To explore the sex-based differences in mental retardation.
• To assess the frequency of X-linked mental retardation in relation to genetic and exogenous causes.

Summary:

• A higher prevalence of boys was observed in the total group (B:G = 1.3) and in those with genetic origins (B:G = 1.4).
• Monogenic forms of mental retardation showed a significant male predominance.
• The frequency of X-linked mental retardation was 12.5% overall, higher in boys (22.1%) and particularly in boys with genetic forms (28.5%).

Impact:

• Highlights the significant role of genetic factors and X-linked inheritance in male mental retardation.
• Provides data for understanding sex differences in intellectual disability.
• Informs genetic counseling and targeted research for male intellectual disability.