New X-linked syndrome of mental retardation gynecomastia, and obesity is linked to DXS255

We describe 14 males from 3 successive generations in a family who have X-linked mental retardation (XLMR), obesity, gynecomastia, speech difficulties, emotional lability, tapering fingers, and small feet. Linkage analysis using markers spread along the X chromosome demonstrated a gene localisation close to the centromere. Maximum lod scores for markers near the centromere, all at θ = 0.00, were 1.36 for DXS7, 4.82 for DXS255, 2.79 for DXS14, 2.09 for DXS72, and 1.46 for DXYS1. The closest flanking markers which showed recombination were DXS84 and DXS94, defining the physical localisation within Xp21.1-q22. DXS255 was fully informative with lod-1 confidence interval for θ of 0.00-0.12. Clinical findings and linkage data in this family distinguish it from the Borjeson-Forssman-Lehmann syndrome and other previously described XLMR syndromes.