Screening for fragile X syndrome in women of reproductive age

• Published in: Prenatal diagnosis 2000-08, Vol.20 (8), p.611-614
• Main Authors: Pesso, Rachel, Berkenstadt, Michal, Cuckle, Howard, Gak, Eva, Peleg, Lea, Frydman, Moshe, Barkai, Gad
• Format: Article
• Language: English
• Subjects: Adult; antenatal screening; DNA - blood; DNA Mutational Analysis; Female; Fetal Diseases - diagnosis; Fetal Diseases - genetics; fragile X syndrome; Fragile X Syndrome - diagnosis; Fragile X Syndrome - genetics; full mutation; general population; Genetic Carrier Screening; Humans; Male; preconceptional screening; Pregnancy; premutation; Prenatal Diagnosis; Prospective Studies; Sex Ratio; Twins
• ISSN: 0197-3851; 1097-0223
• DOI: 10.1002/1097-0223(200008)20:8<611::AID-PD881>3.0.CO;2-M

We conducted a prospective intervention study of screening for fragile X syndrome in the general population. Antenatal and preconceptional screening were carried out in 9459 women aged between 19 and 44 with no known family history of fragile X syndrome. 80% were tested antenatally. 134 carriers were detected (a frequency of 1 in 70); 130 had a premutation (PM) and 4 had a full mutation (FM). Prenatal diagnosis was carried out in 108 concurrent or subsequent pregnancies among carriers involving 111 fetuses. Nine had an FM, a rate of 1 in 12; two of the affected embryos received the FM directly from the mother and in seven it was the result of expansion from a PM. In all cases with an FM the pregnancy was terminated. In PM carriers there was evidence of a selection against the mutated chromosome with a segregation ratio of 0.40. Owing to the high rate of premutated chromosomes in our population we conclude that screening for fragile X syndrome among women of reproductive age should be more widely available. Copyright © 2000 John Wiley & Sons, Ltd.