Læknablaðið : fylgirit - 01.06.1982, Page 48

35
KIGH RISK HLA-Bf HAPLQ- AND GENOTYPES
IN TYPE 1 DIABETES IN ICELAND
Amason, A., Helgason, T. and Jensson, Ó.,
5í)
The Blood Bank, and Diabetic Clinic , University Hospital,
Reykjavik.
A recent ccrtprehensive survey of Type 1 diabetes in
Iceland detected a total of 266 such patients. HLA specific-
ities (A,B,C), Bf and many other genetic markers have present-
ly been ascertained in 172 patients with this type of diabet-
es. In addition HLA-Bf haplo- and genotypes were determined
in 130 of the patients. There were 17 multiplex families in
the study, five of whcan had two affected sibs and 11 with
affected parent and child. Ten HLA-Bf haplotypes increase
the risk of diabetes. Four of these, Al,B8,BfS; A2,B8,BfS;
A2,Bl5,BfS and A3,Bl5,BfS confer the highest risk of type 1
diabetes, especially when these are carried on both chrano-
somes (No 6).
C
The haplotype A2,B8,Bf gives a relative risk of 14
ccmpared with a relative risk of only 1.29 in patients having
the haplotype indicating that the former is a high
risk diabetogenic carrier. VJhen an individual carries two
'high risk' chromosanes the risk of developing the disease is
at its highest.