No evidence for increased mortality in SDHD variant carriers compared with the general population
EUROPEAN JOURNAL OF HUMAN GENETICS
Authors: van Hulsteijn, Leonie T.; Heesterman, Berdine; Jansen, Jeroen C.; Bayley, Jean-Pierre; Hes, Frederik J.; Corssmit, Eleonora P. M.; Dekkers, Olaf M.
Abstract
Germline variants in subunit D of the succinate dehydrogenase gene (SDHD variants) are associated with an increased risk of developing paragangliomas. The aim of this study was to compare mortality rates and survival in a Dutch cohort of SDHD variant carriers with those in the general population. The study was conducted at the Leiden University Medical Center, a tertiary referral center for patients with paragangliomas. Included subjects all tested positive for SDHD variants before 1 July 2012 and visited the departments of Otorhinolaryngology or Endocrinology at least once or had a diagnosed paraganglioma and a SDHD variant-positive family history. Clinical data were retrieved from medical records, information on mortality was obtained from the Municipal Personal Records Database, and mortality rates for the Dutch population were obtained from the Dutch Central Bureau of Statistics, stratified by sex, age and date. SDHD variant carriers were followed from the date of first SDHD variant-related contact until death, emigration or 12 December 2012 and the standardized mortality ratio (SMR) was calculated. Two-hundred and seventy-five SDHD variant carriers were included in the study, of which 80% carried the c.274G>T, p.(Asp92Tyr) variant, had a mean duration of follow-up of 7.6 years, yielding 2242 person-years of observation for analysis. There were 18 deaths in the SDHD variant carrier group; two were paraganglioma related. The SMR for the whole cohort was 1.07 (95% confidence interval 0.67-1.73). In conclusion, mortality in SDHD variant carriers is not substantially increased. Additional studies are required to confirm these findings.
The Succinate Dehydrogenase Genes of the Silkworm, Bombyx mori
SILK, PROTECTIVE CLOTHING AND ECO-TEXTILES
Authors: Xu Shengsheng; Du Fei; Zhang Ze
Abstract
The succinate sehydrogenase (SDH) encoded by nuclear genome is a conjugating enzyme in the inner mitochondrial membrane. It is a junction for oxidative phosphorylation and the electron transport chain.As a part of complex II on the inner mt membranes, the SDH consists of four subunit proteins (A to D). We searched the genome sequence database of Bombyx mori with the Drosophila melanogaste and Nasonia vitripennis SDH by tBlastn and determined the structure of all putative B. mori genes of sdh by DNAMAN. The main results are as follows: The SdhAgene of B. mori contains 13 exons. The lengths of its cDNA is 2 880 bp at least. The SdhB gene of B. mori contains 1 exon only. The lengths of cDNA is 2 847 bp at least. The SdhC gene contains 4 exons. The lengths of cDNA is 714 bp at least. The SdhD gene contains 4 exons, too. The lenghts of cDNA is 1 976 bp at least.