Objective: The depression of the ventilatory and P(0.1 )responses to hypoxia and hypercapnia may play an important role in the development of CO(2) retention in the patients with chronic obstructive pulmonary disease (COPD). The purpose of this study was to investigate if there is any linkage relationship between the depressed ventilatory and P(0.1) response phenotypes and the microsatellite markers on chromosome 6q21.1-21.2 among Chinese people.
Methods: P(0.1) and ventilatory responses to hypoxia were measured in six COPD patients with type II respiratory failure, as well as in their 21 normal adult offsprings. Polymerase chain reaction (PCR), denaturing polyacrylamide gel electrophoresis and silver staining techniques were used to study the amplified fragment length polymorphism. Linkage analysis was done with the LINKAGE program.
Results: Hypoxia response was low in 10 offsprings, and normal in the other 11 offsprings. Linkage analysis showed the maximum Lod score was 1.74(D6S276, theta = 0.10).
Conclusion: The depressed hypoxia response might have been influenced by genetic factors. The model was in accord with autosomal dominant inheritance. The disease-related gene was linked to D6S276 locus.