[Fragile X and autistic mental retardation]

Indeed 1 to 6% of the mental defects are corresponding to the type described by H. Renpenning et al. (1962): long narrow face, bad hem of outturned large ears, blue pale irides; macro-orchidism; mental retardation, quietness, and language's primary defect. 5-60% of their free-folic acid cultured (G.R. Sutherland, 1977) venous lymphocytes show a recessive fragility of the X long arms, in or between q27-28 bands (H. A. Lubs, 1969). It is more difficult to find this chromosomal abnormality among female carriers, even if not too much aged. Only some of these cases (W. T. Brown, 1982) do autistic psychoses, whose origin or expression is the mental defect. We relate two personal cases of it - besides with a large span, as in the so-called "normal" case related by M.G. Daker (1981).