Evidence for a pre-malignant cell line in a skin biopsy from a patient with Nijmegen breakage syndrome.

Background: Nijmegen breakage syndrome is an autosomal recessive disorder characterized by microcephaly, immunodeficiency, hypersensitivity to X-irradiation, and a high predisposition to cancer. Nibrin, the product of the gene, is part of the MRE11/RAD50 (MRN) complex that is involved in the repair of DNA double strand breaks (DSBs), and plays a critical role in the processing of DSBs in immune gene rearrangements, telomere maintenance, and meiotic recombination. NBS skin fibroblasts grow slowly in culture and enter early into senescence.

Trends in prenatal diagnosis of non-specific multiple malformations disorders with reference to the own experience and research study on Smith-Lemli-Opitz syndrome.

Aim Of The Study: Biochemical diagnosis of fetuses with multiple malformations--an attempt to determine the frequency of prenatal Smith-Lemli-Opitz syndrome. Discussion on trends in prenatal diagnosis of non-specific multiple malformations disorders.

Material And Methods: A total of 117 fetal samples were obtained.

Loss of juxtaposition of RAG-induced immunoglobulin DNA ends is implicated in the precursor B-cell differentiation defect in NBS patients.

The Nijmegen breakage syndrome (NBS) is a rare inherited condition, characterized by microcephaly, radiation hypersensitivity, chromosomal instability, an increased incidence of (mostly) lymphoid malignancies, and immunodeficiency. NBS is caused by hypomorphic mutations in the NBN gene (8q21). The NBN protein is a subunit of the MRN (Mre11-Rad50-NBN) nuclear protein complex, which associates with double-strand breaks.

SLOS carrier frequency in Poland as determined by screening for Trp151X and Val326Leu DHCR7 mutations.

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder of cholesterol biosynthesis caused by mutations in the DHCR7 gene. Previous studies estimated the prevalence of SLOS between 1 in 10,000 to 1 in 70,358 based on case frequency surveys. Although panethnic, SLOS appears to be most frequent in Central European populations (Czech Republic 1 in 10,000, Slovakia 1 in 15,000 - 1 in 20,000).

Maternal urinary steroid profiles in prenatal diagnosis of Smith-Lemli-Opitz syndrome: first patient series comparing biochemical and molecular studies.

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder caused by reduced activity of 7-dehydrocholesterol (7DHC) reductase, resulting in a decreased level of cholesterol and increased concentrations of 7DHC and 8DHC in body fluids and tissues. Ten pregnancies at 25% risk of SLOS underwent prenatal testing. Diagnostic studies included DHCR7 mutation analysis in chorionic villus samples, amniotic fluid sterol analysis and serial measurements of oestriol (E3), pregnanetriol (PT), 7-dehydropregnanetriol (7DHPT) and 8-dehydroesteriol (8DHE3) concentrations in maternal urine samples obtained between 9 and 20 weeks of gestation.