Balanced Reciprocal Translocation t(X;1) in a Girl with Tall Stature and Primary Amenorrhea

Abstract

Chromosomal translocations constitute one of the most important, yet uncommon, causes of primary amenorrhea and gonadal dysgenesis. Although X-autosome translocations are frequently associated with streak gonads and clinical features of the Turner syndrome, the majority of X-autosome carriers may present with a variable phenotype, developmental delay, and recognizable X-linked syndrome due to nonrandom X-inactivation. In this article, we describe a healthy 15.5-year-old girl with primary amenorrhea, gonadal dysgenesis, and tall stature without other manifestations of the Turner syndrome. Relevant clinical, biochemical, endocrinological, and cytogenetical evaluations were performed. Initial investigations revealed hypergonadotropic hypogonadism (FSH=134 mIU/mL [normal=10-15 mIU/mL], LH=47.5 [normal=10-15 mIU/mL], and estradiol=24.3 pmol/L). On ultrasound examination of the pelvis, streak ovaries with a hypoplastic uterus were noted. Chromosome study, performed according to routine procedures, revealed an apparently balanced reciprocal translocation involving the short arm of chromosome 1(p2) and the long arm of the X chromosome (q2) in all the cells with the following karyotype: 46,X,t(1;X)(p13;q22). She was placed on hormone replacement therapy. In our patient, X-autosome translocation was associated with gonadal dysgenesis and tall stature. We conclude that t(X;1) may be associated with gonadal dysgenesis without other congenital abnormalities. To our knowledge, normal phenotype with gonadal dysgenesis and tall stature in association with t(X;1) translocation has not been previously reported.

Keywords: Genetic translocation; Gonadal dysgenesis; Turner syndrome.

Figure 1

Karyotype shows a balanced reciprocal translocation between the short arm of chromosome 1 and the long arm of chromosome X:46,X,t(1;X)(p13;q22).