Somatic mosaicism of a novel IKBKG mutation in a male patient with incontinentia pigmenti.

Incontinentia pigmenti (IP) is an X-linked, dominant genodermatosis usually fatal in utero in males. In rare circumstances, survival is possible due to abnormal karyotype or somatic mosaicism. In this report, the mechanism and significance of loss of detectable mutation in peripheral blood leukocytes of a somatic mosaic male is discussed and an alternative approach to achieving molecular diagnosis presented. A male patient is reported, who initially presented at 2 days of age with a rash and seizure. Clinical assessment and histology of a skin biopsy were consistent with a diagnosis of IP. He was subsequently found to have bilateral retinal detachments. Screening for the common deletion in IKBKG was negative. A novel nonsense variant, c.937C>T (p.Gln313*) in IKBKG was identified at an approximate level of 15% in a blood sample taken at 10 days of age, but was undetectable in a sample taken at 3 years most likely due to selective apoptosis of mutant cells. Samples taken from the patient when he was 5-6 years of age identified the mutation at a low level in hair root and urine but not in blood or buccal cells. The detection of the mutation in cells derived from all germ layers indicates a de novo event at an early stage of embryogenesis. This is the first report of a nonsense mutation in a male IP patient.

PLAUR polymorphisms are associated with asthma, PLAUR levels, and lung function decline.

BACKGROUND: Several studies have suggested that chromosome 19q13.1-3 contains asthma susceptibility genes. OBJECTIVE: Linkage and association analyses using 587 United Kingdom and Dutch asthma families (n = 2819 subjects) were used to investigate this region. METHODS: A 3-phase procedure was used: (1) linkage and association analyses using 15 microsatellite markers spanning 14.4 mega base pairs (Mbps) on 19q13, (2) fine mapping of the refined region using 26 haplotype tagging single nucleotide polymorphisms (SNPs), and (3) dense gene analyses using 18 SNPs evaluated for association with asthma, bronchial hyperresponsiveness (BHR), FEV1, plasma urokinase plasminogen activator receptor (PLAUR), and rate of annual FEV1 decline in subjects with asthma. RESULTS: The microsatellite analyses provided tentative support for an asthma/lung function susceptibility locus (48.9-49.1Mbps), and fine mapping localized modest association to the PLAUR gene. PLAUR SNPs in the 5' region, intron 3, and 3' region are associated with asthma and BHR susceptibility and predict FEV1 and plasma PLAUR levels. SNPs in the 5' region showed association for asthma (2 populations), FEV1 (2 populations), and BHR (2 populations) phenotypes. SNPs in intron 3 showed association with asthma (2 populations) and BHR (3 populations). Importantly, the same 5' region and intron 3 SNPs were associated with plasma PLAUR levels. The same 5' region and 3' region SNPs were found to be determinants of FEV1 decline in subjects with asthma. CONCLUSION: This study represents the first report to identify PLAUR as a potential asthma susceptibility gene and determine PLAUR regions underlying this association, including a role in influencing plasma PLAUR levels. Finally, the association of PLAUR with lung function decline supports a role for PLAUR in airway remodeling in asthma.

Mammalian cell survival and processing in supercritical CO(2).

We demonstrate that mammalian cells can survive for 5 min within high-pressure CO(2)(.) Cell survival was investigated by exposing a range of mammalian cell types to supercritical CO(2) (scCO(2)) (35 degrees C, 74 bar; 1 bar = 100 kPa) for increasing exposure and depressurization times. The myoblastic C2C12 cell line, 3T3 fibroblasts, chondrocytes, and hepatocytes all displayed appreciable but varying metabolic activity with exposure times up to 1 min. With depressurization times of 4 min, cell population metabolic activity was >/=70% of the control population. Based on survival data, we developed a single-step scCO(2) technique for the rapid production of biodegradable poly(dl-lactic acid) scaffolds containing mammalian cells. By using optimum cell-survival conditions, scCO(2) was used to process poly(dl-lactic acid) containing a cell suspension, and, upon pressure release, a polymer sponge containing viable mammalian cells was formed. Cell functionality was demonstrated by retention of an osteogenic response to bone morphogenetic protein-2 in C2C12 cells. A gene microarray analysis showed no statistically significant changes in gene expression across 4,418 genes by a single-class t test. A significance analysis of microarrays revealed only eight genes that were down-regulated based on a delta value of 1.0125 and a false detection rate of 0.