Publications by authors named "G A Durrheim"

Article Synopsis
  • The latitudinal diversity gradient (LDG) reflects a global trend showing that species richness typically increases towards the tropics, but understanding its causes has been challenging due to insufficient data.
  • A new high-resolution map of local tree species richness was created using extensive global forest inventory data and local biophysical factors, analyzing around 1.3 million sample plots.
  • Findings indicate that annual mean temperature is a significant predictor of tree species richness, aligning with the metabolic theory of biodiversity, but additional local factors also play a crucial role, especially in tropical regions.
View Article and Find Full Text PDF

Background: Trichohepatoenteric syndrome (THE-S) or phenotypic diarrhoea of infancy is a rare autosomal recessive disorder characterised by severe infantile diarrhoea, facial dysmorphism, immunodeficiency and woolly hair. It was first described in 1982 in two infants with intractable diarrhoea, liver cirrhosis and abnormal hair structure on microscopy. We report on two siblings from a consanguineous family of Somali descent who, despite extensive clinical investigation, remained undiagnosed until their demise.

View Article and Find Full Text PDF

Congenital long QT syndrome (cLQTS) is a genetic disorder predisposing to ventricular arrhythmia, syncope and sudden death. Over 700 different cLQTS-causing mutations in 13 genes are known. The genetic spectrum of LQTS in 44 South African cLQTS patients (23 known to carry the South African founder mutation p.

View Article and Find Full Text PDF

Objectives: The purpose of this study was to assess the pregnancy-related cardiovascular risk in LQT1 patients.

Background: Only 1 study addressed this issue in genotyped patients and reported that the highest risk is for LQT2 patients.

Methods: This case-control study, performed in a cohort of patients from 22 families affected by LQT1 and all sharing the common KCNQ1-A341V mutation, involved 36 mutation carriers and 24 of their unaffected sisters for a total of 182 pregnancies.

View Article and Find Full Text PDF

Background: In the congenital long-QT syndrome (LQTS), there can be a marked phenotypic heterogeneity. Founder effects, by which many individuals share a mutation identical by descent, represent a powerful tool to further understand the underlying mechanisms and to predict the natural history of mutation-associated effects. We are investigating one such founder effect, originating in South Africa in approximately ad 1700 and segregating the same KCNQ1 mutation (A341V).

View Article and Find Full Text PDF