Inherited tandem duplication dup(X) (q131‐q212) in a male proband

Abstract
A tandem duplication dup(X) (q131-q212) was diagnosed neonatally because of the peculiar appearance. Family investigation demonstrated that the duplication has segregated through phenotypically normal female carriers for at least 3 generations. Inactivation studies showed that the aberrant X was preferentially late replicating. The difficulties related to prenatal diagnosis of minor X chormosome aberrations in males are discussed.