Ethnic variability of HIF-1α polymorphisms

The hypoxia-inducible factor-1 alpha (HIF-1 alpha) is a transcription factor that plays a crucial role in the cellular response to hypoxia. The C1772T (P582S) and G1790A (A588T) polymorphisms, within the oxygen dependent degradation domain of HIF-1 alpha protein, seem to be important in the oxygen regulation of protein stability, influencing the progression of some hypoxic solid tumors. Despite the numerous reports about the influence of these single-nucleotide polymorphisms (SNPs) on cancer incidence and progression, there are no published data concerning the interethnic variability of these polymorphisms. Here we investigated the SNPs C1772T and G1790A, in four distinct populations from Portugal, Mozambique, Colombia and Guinea-Bissau. The allelic frequency of the 1772T allele was 0.122 in Portugal, 0.151 in Colombia, 0.246 in Mozambique and 0.08 in Guinea-Bissau. Statistically significant differences were observed when comparing the Portuguese population with the Mozambican one (p = 0.020) and the populations from Mozambique and Guinea-Bissau (p < 0.0001). The Mozambican population had an allelic frequency of 0.006 for the 1790A allele, which was not detected among the other studied populations. In conclusion, there is an ethnicity-related variation in the frequency of C1772T and G1790A polymorphisms of the HIF-1a gene that may be relevant in the context of tumor aggressiveness and progression.