THE FRAGILE X SYNDROME: 13 YEARS OF EXPERIENCE

Fragile x syndrome (fxs; mim #300624; fraxa, xq27.3) is well known and a common cause of x-linked mental retardation. the syndrome is caused by dynamic mutation of fmr1 gene cpg island cgg repeats. clinically fxs patients demonstrate delayed developmental milestones, particularly speech, attention-deficit/hyperactivity disorder, autistic features, and psychomotor development delay. dysmorphic face and macroorchidism are important features in the postpubertal age. we present our 13-year experience with fxs patients who were confirmed by molecular diagnostic. phenotype-genotype evaluation was made for 12 male fxs patients. genotype-phenotype analysis did not reveal significant correlation between clinical symptoms observed in fxs patients and genotypes obtained from leucocytes dna analysis. the prevalence of the fragile x syndrome in the latvian male population was estimated to be 1/6428 (95% ci 5538-7552) or 15.55/100 000 males (95% ci 13.24 – 18.05). the prevalence of the fragile x syndrome among mentally retarded male patients was estimated to be 2.67%. the low number of diagnosed patients with fragile x syndrome demonstrated in our study led to the conclusion that fragile x syndrome is generally clinically unrecognised.