X;1 translocation in a female Menkes patient: characterization by fluorescence in situ hybridization.

Menkes disease is an X-linked recessive disorder of copper metabolism, characterized by progressive neurological degeneration, abnormal hair and connective tissue manifestations. We present a female Menkes patient, with classical Menkes features, carrying a de novo balanced translocation 46,X,t(X;1)(q13;q12). The breakpoint on the X chromosome was narrowed down to Xq13.3 within a 1 Mb YAC contig containing the Menkes gene, using fluorescence in situ hybridization. The translocated X chromosome was of paternal origin and non-randomly active leading to the expression of the disease. This was additional evidence for paternal origin of de novo chromosome rearrangements, including all the X; autosomal translocations examined so far.