Maria Christina Bahiana Olympio da Silva

Genetic and Anthropological Studies in the Island of Itaparica, Bahia, Brazil

The ongoing racial admixture was studied in the island of Itaparica off the coast of the State of Bahia, in Brazil. The following gene frequencies were observed: Hb S = 0.039; Hb C = 0.022; PGD C = 0.024; Gd A = 0.217 and Gd A = 0.052, among 293 mixed school children whose black phenotype index (medium mulatto + dark mulatto + black/total) was 0.457. Data on racial groups, obtained from 898 death certificates of three periods (1889-1890, 1934-1937 and 1975-1980) showed that in about 90 years (three generations) the proportion of mulattoes had doubled, the whites had decreased to one third, and the blacks showed no variation. Changes in the frequencies of surnames within the whites over the same 90 years indicated a growing proportion of individuals with black ancestry flowing into the white group. Higher reproductive rates among the more negroid individuals is probably the leading force directing the racial admixture in the island.

Sickle cell disease does not predispose to caries or periodontal disease.

This study investigated the prevalence of dental caries and periodontal condition in a population with sickle cell disease (SCD), analyzing some associations with disease severity. The Decayed, Missing and Filled Teeth index (DMFT) and Community Periodontal Index (CPI) were recorded for 99 individuals with SCD and 91 matched controls. Socio-demographic status, oral health behaviors, and history of clinical severity of SCD were assessed. Statistical comparisons were performed between the group with SCD and the control group, as well as multivariate logistic regression analyses with DMFT index and CPI as the dependent variables. The mean number of decayed teeth was significantly higher in individuals with HbSS. Older age, female gender, and daily smoking were identified as risk factors for higher DMFT, while older age and absence of daily use of dental floss were risk factors for the development of periodontal disease. In conclusion, risk factors known to cause caries and periodontal disease had more influence on oral health than the direct impact of SCD.

Radiographic changes of the jaws in HbSS and HbSC genotypes of sickle cell disease

This study used panoramic radiographs to evaluate the presence of radiographic changes in the jaws of a population who had sickle cell disease (SCD). The authors compared the frequency of findings between subjects with and without SCD. Panoramic radiographs of 71 subjects with SCD (36 with HbSS and 35 with HbSC) and 52 healthy controls (HbAA) were evaluated for the presence of the following radiographic alterations: radiopaque areas, increased spacing of bony trabeculae, horizontal arrangement of bony trabeculae, and absence of mandibular canal corticalization. The control group had a significantly smaller number of all the radiographic features evaluated. Differences were not statistically significant between the groups with HbSS and HbSC, except for more trabecular spacing in the molar region in the HbSS genotype, suggesting a possible correlation between radiographic findings and disease presentation.

Anthropometric Data of Children Heterozygous for Abnormal Hemoglobins (Hb AS, Hb AC) and Paired Controls Hb AA

No significant difference was found as regards ten anthropometric data in AS and AC children in comparison with AA controls paired for sex, age and race.

Hexokinase activity and isozyme pattern in human placenta: A population study

Abstract Two population samples of human placenta with a different degree of black admixture were studied for hexokinase activity and electrophoretic isozyme pattern. Out of a total of 204 placentas there was no case of either full enzyme deficiency or variation on the electrophoretic pattern. All human placenta exhibited hexokinase type I as compared to a control of hexokinase types I and II from rat heart. The hexokinase activity levels on human placenta showed no effect of the newborn sex or black admixture.