RESUMO
Sardinians, a population with many distinct anthropogenetic features, has been studied for the COLIA1 and COLIA2 genes at the DNA level for two purposes: to look for new RFLPs (restriction fragment length polymorphisms) and to study the distribution of three known COLIA2 RFLPs (EcoRI, RsaI, MspI) at both the allele and the haplotype levels. None of the eleven enzyme-probe systems examined led to the discovery of a new polymorphism. The following frequency q was found for the less common allele of the three RFLPs: EcoRI, q(+) = 0.178 +/- 0.031; RsaI, q(-) = 0.316 +/- 0.038; MspI, q(-) = 0.046 +/- 0.017. EcoRI turned out to be the most discriminant of the three polymorphisms because the frequency of the (+) allele in Sardinians was about half that estimated for a large homogeneous white sample (0.18 +/- 0.03 vs. 0.30 +/- 0.01). So far as the haplotype level is concerned, the sample is made up of triplets (parents and child). Therefore all the haplotype frequencies and delta values (degrees of disequilibrium, D) were obtained by direct counting of the unambiguously identified haplotypes rather than being based on their maximum-likelihood estimates. This together with their analytical and detailed presentation makes these data comparable with future findings, provided that the two data sets are presented in a comparable way. At this level the three RFLPs are efficient in distinguishing Sardinians from Calabrians (southern Italy) but not from the central Italian population. The present results, besides adding a further discriminative criterion between Sardinians and Italians (and whites on the whole), identify the complex COLIA2 locus as a valuable anthropogenetic marker.
Assuntos
Colágeno/genética , DNA/genética , Antropologia Física , Enzimas de Restrição do DNA , Feminino , Frequência do Gene , Marcadores Genéticos , Haplótipos , Humanos , Itália , Masculino , Polimorfismo de Fragmento de RestriçãoAssuntos
Infecções Bacterianas/etiologia , Deficiência de Glucosefosfato Desidrogenase/complicações , Infecções Bacterianas/epidemiologia , Febre Botonosa/epidemiologia , Febre Botonosa/etiologia , Criança , Feminino , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Humanos , Itália/epidemiologia , Masculino , Meningite/epidemiologia , Meningite/etiologia , Estudos Retrospectivos , Febre Tifoide/epidemiologia , Febre Tifoide/etiologiaRESUMO
We determined the activity level of glucose 6-phosphate dehydrogenase in 467 patients with cataract from northern Sardinia. Of 226 men, 18 (8%) had glucose 6-phosphate dehydrogenase deficiency. Of 241 women, 30 (12%) were heterozygous and two (1%) were homozygous for glucose 6-phosphate dehydrogenase deficiency. These prevalences were not significantly different from those expected in the general population. We concluded that patients with glucose 6-phosphate dehydrogenase deficiency do not have a higher risk of developing cataract.
