[Encephalopathy related to X fragility: neither inactivation nor deletion of the distal fragment q28 to qter. Enzymatic and morphometric evidence].
Hypothesis on the nature of the fragile site Xq28 and its relations with the specific phenotype are discussed. The roles of a local inactivation (tested by G6-PD activity in 9 patients) or of a deletion Xq28 leads to qter (studied by morphometric evaluations on 2 patients and their heterozygotic mother) are not confirmed.