The first prenatal diagnosis for veno-occlusive disease and immunodeficiency syndrome, an autosomal recessive condition associated with mutations in SP110
PRENATAL DIAGNOSIS
Authors: Cliffe, Simon T.; Wong, Melanie; Taylor, Peter J.; Ruga, Ezia; Wilcken, Bridget; Lindeman, Robert; Buckley, Michael F.; Roscioli, Tony
Abstract
Objectives We present the first prenatal diagnosis of familial hepatic veno-occlusive disease with immunodeficiency (VODI). Homozygous mutations in the gene SP110 are the genetic basis of VODI. The proband in this report presented at three months of age with hepatomegaly hepatic failure and was found to have hypogammaglobulinemia. He died one month after hepatic transplant at eight months of age due to hemophagocytic syndrome. DNA testing detected a homozygous truncating mutation in exon 5; SP110 c.642delC. Prenatal testing was offered to this family in a subsequent pregnancy. Methods Chorion villus was sampled at 12 weeks' gestation. DNA was extracted using standard techniques, and sequencing of SP110 exon 5 was performed using flanking primers. Maternal contamination was excluded by examining STR markers in CVS and maternal DNA. Results A heterozygous SP110 c.642delC mutation was detected in exon 5. This mutation was present in heterozygous form in both parents. Conclusions The prenatal test result is predictive of a child with a normal immune and hepatic phenotype. This report presents the first prenatal molecular diagnosis for VODI and shows the importance of molecular genetic research in not only defining the aetiology of syndromes but also in assisting reproductive choices through the collaboration of genetic and feto-maternal services. Copyright (c) 2007 John Wiley & Sons, Ltd.
Identification of potential HIV restriction factors by combining evolutionary genomic signatures with functional analyses
RETROVIROLOGY
Authors: McLaren, Paul J.; Gawanbacht, Ali; Pyndiah, Nitisha; Krapp, Christian; Hotter, Dominik; Kluge, Silvia F.; Goetz, Nicola; Heilmann, Jessica; Mack, Katharina; Sauter, Daniel; Thompson, Danielle; Perreaud, Jeremie; Rausell, Antonio; Munoz, Miguel; Ciuffi, Angela; Kirchhoff, Frank; Telenti, Amalio
Abstract
Background: Known antiretroviral restriction factors are encoded by genes that are under positive selection pressure, induced during HIV-1 infection, up-regulated by interferons, and/or interact with viral proteins. To identify potential novel restriction factors, we performed genome-wide scans for human genes sharing molecular and evolutionary signatures of known restriction factors and tested the anti-HIV-1 activity of the most promising candidates. Results: Our analyses identified 30 human genes that share characteristics of known restriction factors. Functional analyses of 27 of these candidates showed that over-expression of a strikingly high proportion of them significantly inhibited HIV-1 without causing cytotoxic effects. Five factors (APOL1, APOL6, CD164, TNFRSF10A, TNFRSF10D) suppressed infectious HIV-1 production in transfected 293T cells by >90% and six additional candidates (FCGR3A, CD3E, OAS1, GBP5, SPN, IFI16) achieved this when the virus was lacking intact accessory vpr, vpu and nef genes. Unexpectedly, over-expression of two factors (IL1A, SP110) significantly increased infectious HIV-1 production. Mechanistic studies suggest that the newly identified potential restriction factors act at different steps of the viral replication cycle, including proviral transcription and production of viral proteins. Finally, we confirmed that mRNA expression of most of these candidate restriction factors in primary CD4+ T cells is significantly increased by type I interferons. Conclusions: A limited number of human genes share multiple characteristics of genes encoding for known restriction factors. Most of them display anti-retroviral activity in transient transfection assays and are expressed in primary CD4+ T cells.