Researchers uncover genetic features of LADA diabetes

An international collaboration of researchers has identified a number of genetic features of LADA diabetes which could help ensure that adults developing diabetes are correctly diagnosed and treated.
LADA stands for latent autoimmune diabetes of adulthood and is sometimes referred to type 1.5 diabetes as it has been thought to have features of both type 1 diabetes and type 2.
LADA is known to be an autoimmune disease which requires people with the condition to ultimately go onto insulin. However, as it is diagnosed into adulthood and often may not require insulin treatment at first, it may sometimes be mistaken for type 2 diabetes.
The research, led by Dr. Struan Grant of the Children’s Hospital of Philadelphia, used genetic analysis to uncover which genetic loci were features of the condition.
The analysis involved DNA samples from 978 people with LADA and these samples were compared to people without diabetes, which consisted of 1,057 children and 2,820 adults.
Their findings primarily showed that LADA has more in common genetically with type 1 than type 2 diabetes. One exception to this was in the HNF1A locus which is associated with type 2 diabetes. On the other hand, people LADA had a low frequency of the type 2 diabetes risk allele of the TCF7L2 locus.
In conclusio, the researchers noted that LADA is genetically closer to type 1 diabetes than type 2 but that the genetic load of type 1 diabetes risk alleles is less strong than it is in children with type 1 diabetes.
Dr Grant stated that: “Our finding that LADA is genetically closer to type 1 diabetes than to type 2 diabetes suggests that some proportion of patients diagnosed as adults with type 2 diabetes may actually have late-onset type 1 diabetes.”
This has clinical implications in that it shows that GPs will need to take care to ensure adults presenting with diabetes are given the correct diagnosis.
The article is published by the BMC Medicine journal.