[Racial influence on the ventilatory response to hypoxia and hypercapnia (author's transl)]

The ventilatory response to hypoxia isocapnic test and to CO2 stimulation in normoxic conditions was measured at rest in 42 sea level subjects. They were classified according to their ancestry in four racial groups: Caucasian, Negro, Mongolian and Mestizo. There was no difference in the response of ventilation to CO2 between the groups. However the response of ventilation to hypoxia was statistically significant, lower in the Mongolian and Mestizo groups than in the Caucasian and Negro ones. All the variables measured were similar in the Mongolian and Mestizo groups. Caucasians showed the lowest resting ventilation and Negroes showed the lowest resting heart rate. Statistically, each of these parameters was significantly different from the other groups. It is concluded that the ventilatory differences observed reflect differences in their peripheral chemoreceptor sensitivity to hypoxia, and they may explain the large variation of ventilatory responses to hypoxia found by different investigators. The similar values found in all parameters measured in the Mongolian and Mestizo groups are explained by the ancestral link between these races.