Mapping of the locus for X-linked cardioskeletal myopathy with neutropenia and abnormal mitochondria (Barth syndrome) to Xq28.

X-linked cardioskeletal myopathy with neutropenia and abnormal mitochondria is clinically characterized by congenital dilated cardiomyopathy, skeletal myopathy, recurrent bacterial infections, and growth retardation.We analyzed linkage between the disease locus and X-chromosomal markers in a family with seven carriers, four patients, and eight unaffected sons of carriers.Highest lod scores obtained by two-point linkage analysis were 2.70 for St14.1 (DXS52, TaqI) at a recombination fraction of zero and 2.53 for cpX67 (DXS134) at a recombination fraction of zero.Multipoint linkage analysis resulted in a maximum lod score of 5.24 at the position of St35.691 (DXS305).The most distal recombination detected in this family was located between the markers II-10 (DXS466) and DX13 (DXS15).These data indicate the location of the mutated gene at Xq28.