Trisomy 21 is a cause of permanent neonatal diabetes that is autoimmune but not HLA associated
De Franco, Elisa
Flanagan, Sarah E.
Hattersley, Andrew T.
PublisherAmerican Diabetes Association
MetadataShow full item record
Identifying new causes of permanent neonatal diabetes (diagnosis <6 months; PNDM) provides important insights into β-cell biology. Patients with Down syndrome (DS) resulting from trisomy 21 are 4 times more likely to have childhood diabetes with an intermediate HLA association. It is not known if DS can cause PNDM. We found trisomy 21 was 7 times more likely in our PNDM cohort than in the population (13/1522 = 85/10,000 observed vs. 12.6/10,000 expected) and none of the 13 DS-PNDM cases had a mutation in the known PNDM genes which explained 82.9% of non-DS PNDM. Islet autoantibodies were present in 4/9 DS-PNDM patients but DS-PNDM was not associated with polygenic susceptibility to type 1 diabetes. We conclude that trisomy 21 is a cause of autoimmune PNDM that is not HLA associated. We propose that autoimmune diabetes in DS is heterogeneous and includes coincidental type 1 diabetes that is HLA associated and diabetes caused by trisomy 21 that is not HLA associated.