FISH can be used to detect deletions of 4p16.3, the critical region for the phenotype [MISCELLANEOUS] Size of deletion varies from cytogenetically visible deletions to undetectable cytogenetic deletions [MISCELLANEOUS] Sex ratio 2 females to 1 male [MISCELLANEOUS] Contiguous gene deletion syndrome [MISCELLANEOUS] Approximately 35% of patients die during the first 2 years of life [MISCELLANEOUS] Due to hemizygous deletion of 4p16.3 [MOLECULAR BASIS] The frequency is estimated at 1/20,000 to 1/50,000 births [MISCELLANEOUS] De novo deletions in 87% of patients (preferentially paternally derived) [MISCELLANEOUS] 13% of cases secondary to familial translocation (often maternally derived) [MISCELLANEOUS]
|