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- What are the various subtypes of MODY?
Various subtypes of MODY are classified on the basis of mutations in genes
implicated in the development of the pancreas, insulin synthesis, and secretion.
The different subtypes of MODY are summarized in the table given below.Types Gene Function
MODY 1 Hepatocyte nuclear factor-4α (HNF 4A) Transcription factor
MODY 2 Glucokinase (GCK) Glycolytic enzyme
MODY 3 Hepatocyte nuclear factor-1α (HNF 1A) Transcription factor
MODY 4 Insulin promoter factor 1/pancreas–duodenum homeobox
protein 1 (IPF1/PDX1)Transcription factorMODY 5 Hepatocyte nuclear factor-1β (HNF 1 B) Transcription factor
MODY 6 Neurogenic differentiation 1 (NEUROD1) Transcription factor
MODY 7 Kruppel-like factor 11 (KLF11) Transcription factor
MODY 8 Carboxyl ester lipase (CEL) Lipase
MODY 9 Paired-box gene 4 (PAX4) Transcription factor
MODY 10 Insulin (INS) Insulin
MODY 11 Tyrosine kinase, B-lymphocyte specific (BLK) Transcription factor- What is the most common form of MODY?
Among the various subtypes of MODY, type 3 is the most common form.
MODY 3 is due to inactivating mutations in HNF 1A gene, which result in
reduced β-cell mass and impaired insulin secretion. During adolescence and
early adulthood, these individuals have normal fasting plasma glucose, but have
hyperglycemia during oral glucose tolerance test. However, patients with
MODY 3 show progressive decline in β-cell function and have a high preva-
lence of microvascular complications. The characteristic features of MODY 3
include low renal threshold for glucose (renal glycosuria), increased proinsulin
to insulin ratio, and good therapeutic response to sulfonylureas. Renal glycos-
uria in these patients is possibly related to decrease in SGLT 2 expression,
which is also regulated by HNF 1A gene.- How to differentiate MODY from type 2 diabetes?
As both MODY and type 2 diabetes can present in young individuals with non-
ketotic hyperglycemia, it is important to differentiate between them as these12 Diabetes in the Young