Evidence for a major gene affecting the transition from normoglycaemia to hyperglycaemia in Psammomys obesus

J. Hillel, D. Gefel, R. Kalman, G. Ben-Ari, L. David, O. Orion, M. W. Feldman, H. Bar-On, S. Blum, I. Raz, T. Schaap, I. Shpirer, U. Lavi, E. Shafrir, E. Ziv

Research output: Contribution to journalArticlepeer-review

Abstract

We investigated the mode of inheritance of nutritionally induced diabetes in the desert gerbil Psammomys obesus (sand rat), following transfer from low-energy (LE) to high-energy (HE) diet which induces hyperglycaemia. Psammomys selected for high or low blood glucose level were used as two parental lines. A first backcross generation (BC1) was formed by crossing F 1 males with females of the diabetes-prone line. The resulting 232 BC1 progeny were assessed for blood glucose. All progeny were weaned at 3 weeks of age (week 0), and their weekly assessment of blood glucose levels proceeded until week 9 after weaning, with all progeny maintained on HE diet. At weeks 1 to 9 post weaning, a clear bimodal distribution statistically different from unimodal distribution of blood glucose was observed, normoglycaemic and hyperglycaemic at a 1:1 ratio. This ratio is expected at the first backcross generation for traits controlled by a single dominant gene. From week 0 (prior to the transfer to HE diet) till week 8, the hyperglycaemic individuals were significantly heavier (4-17%) than the normoglycaemic ones. The bimodal blood glucose distribution in BC1 generation, with about equal frequencies in each mode, strongly suggests that a single major gene affects the transition from normo- to hyperglycaemia. The wide range of blood glucose values among the hyperglycaemic individuals (180 to 500 mg/dl) indicates that several genes and environmental factors influence the extent of hyperglycaemia. The diabetes-resistant allele appears to be dominant; the estimate for dominance ratio is 0.97.

Original languageEnglish
Pages (from-to)158-165
Number of pages8
JournalHeredity
Volume95
Issue number2
DOIs
StatePublished - Aug 2005
Externally publishedYes

Keywords

  • Backcross
  • Bimodal distribution
  • Major gene
  • Psammomys obesus
  • QTL
  • Type-2 diabetes

Fingerprint

Dive into the research topics of 'Evidence for a major gene affecting the transition from normoglycaemia to hyperglycaemia in Psammomys obesus'. Together they form a unique fingerprint.

Cite this