Objective evaluation of facial features in Congolese newborns by facial measurements. The need for population-specific measurements.

The evaluation of dysmorphism is often subjective because many continuous traits are not easily measured or lack normal values. Because many common morphologic profiles vary between populations, population-specific reference ranges of relevant traits are needed. We aim to evaluate the objective assessment of facial dysmorphism in 553 Congolese newborns based on facial measurements. Measurements taken with a ruler were on average larger compared to those with a caliper, but the bias did not depend on the size of the measurement. We therefore introduced a correction factor that allows to use both techniques for facial measurements interchangeably in future studies. The outer canthal distance, palpebral fissure length, and mouth width were significantly larger in Congolese newborns (respectively mean 6.59 [SD 0.48]; mean 2.20 [SD 0.24]; mean 2.78 [SD 0.26]) when compared to references based on European newborns (respectively mean 3.59 [SD 1.76]; mean 4.20 [SD 2.26]; mean 0.47 [SD 1.21]), while the rest of measurements were significantly smaller. The interpupillary distance (IPD) calculated from inner canthal distance and outer canthal distance was not significantly different. We observed a poor agreement between clinical evaluation and measured features (kappa of 0.432). Clinicians were more likely to recognize a face as having wide-spaced eyes when it had been recognized as such during the clinical examination, more than if the child had a high interpupillary distance. This suggests that the measured IPD is not precisely reflecting what is clinically evaluated as wide-spaced eyes.

Protective BCL11A and HBS1L-MYB polymorphisms in a cohort of 102 Congolese patients suffering from sickle cell anemia.

BACKGROUND: We aimed to investigate the distribution of selected BCL11A and HMIP polymorphisms (SNP's), and to assess the correlation with HPFH in a cohort of sickle cell patients. METHODS: A preliminary cross-sectional study was conducted in 102 patients. Group 1 was composed of patients with HPFH and Group 2 consisted of patients without HbF. We assessed 8 SNPs previously associated with HPFH in cohorts genetically close to the Congolese population. Observed frequencies were compared to expected frequencies. RESULTS: In the group 1, at rs7606173, the observed frequency for the genotype GG was significantly higher and the genotype GC was significantly lower than their respective expected frequencies. At rs9399137, the observed frequency of the genotype TT was significantly lower than expected. Conversely, the observed frequency of the genotype TC was significantly higher than expected. The observed frequency of the genotype TT at rs11886868 was significantly lower than the expected whereas the frequency of the genotype TC was significantly higher than observed. The lowest HbF level was recorded in patients with genotype CC at rs11886868. CONCLUSION: In this preliminary study, the results demonstrate that alleles of some of the 8 studied SNPs are not randomly distributed among patients with or without HPFH in this cohort.