THE MANIFESTATION OF GENOTYPES RESPONSIBLE FOR BLOOD PRESSURE AND BLOOD SUGAR LEVEL

抄録

It has been known for a long time that hypertension and diabetes mellitus are often complicated by each other. The aim of this paper was to disclose possible causes of such complications by investigating 1) whether or not hypertension and diabetes mellitus are entirely two independent diseases, 2) whether or not they occur together only by chance, 3) whether or not there are some causal factors which are shared by these two diseases and 4) whether or not these two diseases occur together with some probability. The genetic analyses of these two diseases were carried out on the basis of the genetic analyses on blood pressures (BP) and blood sugar levels (BS) in the present studies. It was proved that the genotypic correlation coefficients of BP and BS ranged from 0.075 to 0.573 with a mean value of 0.337 and their environmental correlation coefficients were from -0.029 to -0.337 with a mean value of -0.164. These results suggest that 1) the respective polygenic systems responsible for BP (hypertension) and BS (diabetes mellitus) have multiple effects and 2) the environmental factors responsible for BP and BS have inverse effects. The negative values of the environmental correlation coefficients between BP and BS indicate that the environmental factors which lower BP may elevate BS, and vice versa. An induction of an abnormal glucose tolerance as one of the side effects of thiazides, the most widely used anti-hypertensive diuretics, coincides with the inverse environmental correlation between BP and BS. This finding may be of great importance in the field of clinical genetics.