Categories: Haematopoietic system phene

Mendelian trait/disorder: yes

Mode of inheritance: Autosomal co-dominant

Disease-related: yes

Key variant known: no

Cross-species summary: Glutathione is a small peptide consisting of just three amino acids: glutamic acid, cystein, and glycine. It is a widely-distributed molecule, serving as a reducing agent in many different metabolic processes. One of its most notable roles is in protecting red blood cells from oxidation and haemolysis. Glutathione normally exists in its reduced sulphydral form (GSH; often called reduced glutathione). Its oxidised form consists of two GSH molecules whose cysteines are joined by a di-sulphide bridge (symbolised GSSG). Unlike most peptides, glutathione is not the product of a gene; instead, it is manufactured from its three constituent amino acids in a two-step process catalysed by gamma-glutamylcysteine synthetase (GCS; which creates a di-peptide of glutamic acid and cysteine) and glutathione synthetase (GSHS; which adds glycine). Oxidation of GSH to GSSG is catalysed by glutathione peroxide (GPX); reduction back to GSH is catalysed by glutathione reductase (GR). In the type of deficiency of reduced glutathione described in this entry, all aspects of glutathione metabolism function normally. But a defect in the transport of cysteine across the erythrocyte membrane results in a deficiency of this vital component of GSH, and hence in a deficiency of GSH.

Species-specific description: This form of reduced glutathione deficiency has been reported in Finn and Awassi sheep (Young, 1983).

Breeds: Awassi (Sheep) (VBO_0001308), Finnish Landrace (Sheep) (VBO_0001414).
Breeds in which the phene has been documented. (If a likely causal variant has been documented for the phene, see the variant table breeds in which the variant has been reported).