INS and type 2 diabetes mellitus: ARNT mRNA levels in transformed lymphocytes did not differ between 8 European American control individuals and cell lines from their 8 type 2 diabetic siblings, either when grown under normoglycemic conditions (ARNT to 18 S RNA ratio 0.958, range 0.611–1.285 in controls vs 1.067, range 0.446 – 1.555 in diabetic cell lines; p = 0.40) or when cultured in 28 mM glucose and 5 nmol/l insulin (0.8131.067, range 0.449–1.164 in controls; 0.946, range 0.400 – 2.329 in type 2 diabetes; p = 0.67).