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Multiplexed assessment of human glucokinase variant activity

ABSTRACT: Diabetes is a complex genetic disease affecting millions of people worldwide. A common monogenic form of diabetes is glucokinase (GCK) maturity-onset diabetes of the young (GCK-MODY), which is caused by heterozygous inactivating variants in the gene encoding GCK. GCK catalyzes the phosphorylation of glucose and is known as the pancreatic glucose sensor. Patients with GCK-MODY, in contrast to other diabetics, often do not require treatment but are frequently misdiagnosed and treated unnecessarily. Genetic testing can prevent this, but is hampered by the challenge of interpreting genetic variants. To address this challenge, we generated a comprehensive map of human GCK variant activity. The activity map includes 97% of the possible missense and nonsense variants and correlate with in vitro catalytic efficiency, fasting glucose levels in patients and evolutionary conservation analysis. Activity scores include both hyper- and hypoactive variants.

ORGANISM(S): synthetic construct

PROVIDER: GSE198878 | GEO | 2022/06/16

REPOSITORIES: GEO

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