Screening of rural children in West Bengal for fragile-X syndrome

Area of Science:

• Genetics
• Pediatrics
• Public Health

Background:

• Fragile X syndrome (FRAXA) is a leading genetic cause of intellectual disability.
• Previous FRAXA screening primarily focused on individuals already diagnosed with intellectual disability.
• The prevalence of FRAXA in rural populations remains understudied.

Purpose of the Study:

• To determine the prevalence of Fragile X syndrome (FRAXA) in a rural child population in West Bengal.
• To investigate the frequency of FRAXA among children exhibiting scholastic backwardness or developmental delays.

Main Methods:

• A large-scale survey of 38,803 rural children in West Bengal was conducted between 2004-2007.
• 179 children with scholastic backwardness were selected for expert evaluation (child psychiatrist, psychologist, pediatrician, special educator).
• Molecular and cytogenetic analyses, including CGG repeat identification and FMR1 gene promoter methylation, were performed on blood samples.

Main Results:

• No cases of Fragile X syndrome (FRAXA) were detected in the screened population (0% frequency).
• Among the 179 evaluated children, 140 had non-syndromic intellectual disability (mild, moderate, severe) and 20 had developmental delay.
• Other diagnoses included Down syndrome (6 children) and cerebral palsy (1 child).

Conclusions:

• The study indicates a low prevalence of Fragile X syndrome (FRAXA) in the studied rural West Bengal population.
• Familial disorders like FRAXA appear to be less common in this demographic group.
• The findings contribute to understanding the epidemiology of intellectual disability and its genetic causes in diverse populations.