Síndrome de temblor y ataxia asociado a síndrome del cromosoma X frágil: un nuevo tipo de ataxia cerebelosa asociada a los portadores del síndrome del cromosoma X frágil

Fundamento y objetivo

Uno de cada 1.233 varones y una de cada 411 mujeres son portadores de la premutación del gen FMR1, causante del síndrome X frágil (SXF). Estos portadores, durante su vida, pueden presentar un tipo de ataxia cerebelosa llamada FXTAS (fragile X tremor ataxia syndrome

Background and objectives

It has been estimated that 1:1233 males and 1:411 females are FMR1 premutated carriers. This gene is responsible for the fragile X syndrome.

Patients and method

Among 398 fragile X syndrome families, we evaluated 112 premutated carriers older than 50 year.

Results

FXTAS penetrance among fragile X families was 10.7% for female premutated carriers and 29.7% for male premutated carriers. In the general population, it was estimated that 1:4,000 females and 1:5,000 males will develop the FXTAS syndrome.

Conclusions

Besides the risk for fragile X syndrome, the genetic counseling in premutation carriers should mention the risk for FXTAS. This syndrome should also be taken into account among spinocerebelar ataxia patients with an unknown etiology.