Four novel RSK2 mutations in females with Coffin-Lowry syndrome.

Coffin-Lowry syndrome (CLS) is an X-linked semi-dominant disorder caused by mutations in the RSK2 gene and characterized by moderate to severe mental retardation, characteristic facial features, skeletal deformities, and tapering fingers in males. Females are usually much more mildly and variably affected thus more difficult to diagnose. In this study, molecular genetic analysis was carried out in four female patients presenting features of Coffin-Lowry syndrome. The probands were sporadic cases with no affected males in their families. The molecular analysis of the RSK2 gene revealed four novel mutations, including two frameshift and one missense mutation identified by sequencing, and one large deletion detected by multiplex ligation-dependent probe amplification (MLPA) analysis. Females exhibited a random X-chromosome inactivation pattern. To our knowledge, this is the first report of applying MLPA in the diagnostics of CLS and the first description of a large deletion in a CLS female. These results support including screening for large rearragements in the genetic analysis of female CLS patients.

High prevalence of primary ovarian insufficiency in girls and young women with Nijmegen breakage syndrome: evidence from a longitudinal study.

CONTEXT: Nijmegen breakage syndrome (NBS) is a severe chromosomal instability disorder characterized by microcephaly, growth retardation, immune deficiency, and predisposition for malignancy. It is caused by hypomorphic mutations in the NBN gene, which product belongs to the protein complex critical for processing DNA double-strand breaks during mitotic and meiotic recombination. Data on gonadal function in patients with NBS are limited. OBJECTIVE: Growth and sexual development, along with hormonal assays, were evaluated in girls and young women with NBS homozygous for c.657_661del5 mutation. STUDY DESIGN AND PATIENTS: The group comprised 37 girls and young women with NBS (ages, 0.17-24.25 yr), followed between 1993 and 2008. Patients were divided into three age groups: 1) 1-3 yr; 2) 4-9 yr; and 3) 10 yr and older. Growth, puberty, concentrations of gonadotropins and 17-beta-estradiol, bone age, and pelvic ultrasound were assessed. RESULTS: None of the patients presented a typical growth spurt; the adult height ranged between the 3rd and 25th centiles. Median bone age was delayed by 4.05 yr. Pubarche reached stadium P2 in eight patients and P3 in two patients. In all but one girl, thelarche did not exceed Th2, with low 17beta-estradiol levels. Gonadotropin levels showed a biphasic pattern, with median FSH values of 55.0, 10.9, and 81.9 IU/liter, and LH of 3.2, 0.8, and 21.0 IU/liter in consecutive age groups. Ultrasound visualized small ovaries or solid streaks and the hypoplastic uterus. CONCLUSIONS: Primary ovarian insufficiency and the associated hypergonadotropic hypogonadism are hallmark manifestations in girls and young women with NBS. Our findings emphasize the need for long-term endocrinological and interdisciplinary supervision of these patients.

Trisomy 22pter-q12.3 presenting with hepatic dysfunction variability of cat-eye syndrome.

We describe the clinical characteristics of two patients with cat-eye syndrome (CES, MIM #115470) resulting from a supernumerary marker chromosome that includes 22pter-q12.3. They both presented a constellation of features typical of CES, including coloboma, auricular malformations, heart and renal anomalies, as well as hepatic dysfunction, which led to severe effects. In one case Pierre Robin sequence was diagnosed which has not been described earlier in this trisomy. Although CES is a well known, but infrequently diagnosed disorder, we draw attention both to its clinical overlaps with other disorders and, in view of the clinical variability being identified within the 22q11 region, to the importance of careful molecular examination of proximal 22q in patients with suggestive clinical signs.