48 HOURS. 10/11/1990

The Fragile X Mystery - stories about inherited mental retardation. 1) Family Ties - a Colorado family gathers to learn who carries the defective X chromosome and what it means. 2) Fragile Ties - a woman with two fragile X children; one institutionalised, the other behaving unpredictably. 3) Handle With Care - what can be done for children with fragile X if diagnosed early; no cure in sight. 4) The Choice - couple facing the decision whether to have children once the mother is diagnosed as a carrier. 5) The Journey - a woman's young daughter begins therapy for fragile X. 6) On The Edge - woman with fragile X, and child also. 6) Fitting In - retarded people leading normal lives.