Browsing by Author "Graves, Tamara J."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Fine mapping and expression of candidate genes within the chromosome 10 QTL region of the high and low alcohol-drinking rats
    (ScienceDirect, 2010-09) Bice, Paula J.; Liang, Tiebing; Zhang, Lili; Graves, Tamara J.; Carr, Lucinda G.; Lai, Dongbing; Kimpel, Mark W.; Foroud, Tatiana; Medicine, School of Medicine
    The high and low alcohol-drinking (HAD and LAD) rats were selectively bred for differences in alcohol intake. The HAD/LAD rats originated from the N/Nih heterogeneous stock developed from intercrossing eight inbred rat strains. The HAD×LAD F2 were genotyped, and a powerful analytical approach, using ancestral recombination and F2 recombination, was used to narrow a quantitative trait loci (QTL) for alcohol drinking to a 2-cM region on distal chromosome 10 that was in common in the HAD1/LAD1 and HAD2/LAD2 analyses. Quantitative real-time PCR was used to examine mRNA expression of six candidate genes (Crebbp, Trap1, Gnptg, Clcn7, Fahd1, and Mapk8ip3) located within the narrowed QTL region in the HAD1/LAD1 rats. Expression was examined in five brain regions, including the nucleus accumbens, amygdala, caudate putamen, hippocampus, and prefrontal cortex. All six genes showed differential expression in at least one brain region. Of the genes tested in this study, Crebbp and Mapk8ip3 may be the most promising candidates with regard to alcohol drinking.
  • Thumbnail Image
    Item
    Identification and validation of a novel pathogenic variant in GDF2 (BMP9) responsible for hereditary hemorrhagic telangiectasia and pulmonary arteriovenous malformations
    (Wiley, 2022) Balachandar, Srimmitha; Graves, Tamara J.; Shimonty, Anika; Kerr, Katie; Kilner, Jill; Xiao, Sihao; Slade, Richard; Sroya, Manveer; Alikian, Mary; Curetean, Emanuel; Thomas, Ellen; McConnell, Vivienne P. M.; McKee, Shane; Boardman-Pretty, Freya; Devereau, Andrew; Fowler, Tom A.; Caulfield, Mark J.; Alton, Eric W.; Ferguson, Teena; Redhead, Julian; McKnight, Amy J.; Thomas, Geraldine A.; Genomics England Research Consortium; Aldred, Micheala A.; Shovlin, Claire L.; Medicine, School of Medicine
    Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant multisystemic vascular dysplasia, characterized by arteriovenous malformations (AVMs), mucocutaneous telangiectasia and nosebleeds. HHT is caused by a heterozygous null allele in ACVRL1, ENG, or SMAD4, which encode proteins mediating bone morphogenetic protein (BMP) signaling. Several missense and stop-gain variants identified in GDF2 (encoding BMP9) have been reported to cause a vascular anomaly syndrome similar to HHT, however none of these patients met diagnostic criteria for HHT. HHT families from UK NHS Genomic Medicine Centres were recruited to the Genomics England 100,000 Genomes Project. Whole genome sequencing and tiering protocols identified a novel, heterozygous GDF2 sequence variant in all three affected members of one HHT family who had previously screened negative for ACVRL1, ENG, and SMAD4. All three had nosebleeds and typical HHT telangiectasia, and the proband also had severe pulmonary AVMs from childhood. In vitro studies showed the mutant construct expressed the proprotein but lacked active mature BMP9 dimer, suggesting the mutation disrupts correct cleavage of the protein. Plasma BMP9 levels in the patients were significantly lower than controls. In conclusion, we propose that this heterozygous GDF2 variant is a rare cause of HHT associated with pulmonary AVMs.