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Variation in the shape of the human face and in stature is determined by complex interactions between genetic and environmental influences. One such environmental influence is malnourishment, which can result in growth faltering, usually diagnosed by means of comparing an individual's stature with a set of age-appropriate standards. These standards for stature, however, are typically ascertained in groups where people are at low risk for growth faltering. Moreover, genetic differences among populations with respect to stature are well established, further complicating the generalizability of stature-based diagnostic tools. In a large sample of children aged 5-19 years, we obtained high-resolution genomic data, anthropometric measures and 3D facial images from individuals within and around the city of Mwanza, Tanzania. With genome-wide complex trait analysis, we partitioned genetic and environmental variance for growth outcomes and facial shape. We found that children with growth faltering have faces that look like those of older and taller children, in a direction opposite to the expected allometric trajectory, and in ways predicted by the environmental portion of covariance at the community and individual levels. The environmental variance for facial shape varied subtly but significantly among communities, whereas genetic differences were minimal. These results reveal that facial shape preserves information about exposure to undernourishment, with important implications for refining assessments of nutritional status in children and the developmental-genetics of craniofacial variation alike., (© 2017 Anatomical Society.)

Background: Orofacial clefts (cleft lip/palate; CL/P) are among the most common congenital anomalies, with prevalence that varies among different ethnic groups. Craniofacial shape differences between individuals with CL/P and healthy controls have been widely reported in non-African populations. Knowledge of craniofacial shape among individuals with non-syndromic CL/P in African populations will provide further understanding of the ethnic and phenotypic variation present in non-syndromic orofacial clefts., Methods: A descriptive cross-sectional study was carried out at Bugando Medical Centre, Tanzania, comparing individuals with unrepaired non-syndromic CL/P and normal individuals without orofacial clefts. Three-dimensional (3D) facial surfaces were captured using a non-invasive 3D camera. The corresponding 3D coordinates for 26 soft tissue landmarks were used to characterize facial shape. Facial shape variation within and between groups, based on Procrustes superimposed data, was studied using geometric morphometric methods., Results: Facial shape of children with cleft lip differed significantly from the control group, beyond the cleft itself. The CL/P group exhibited increased nasal and mouth width, increased interorbital distance, and more prognathic premaxillary region. Within the CL/P group, PCA showed that facial shape variation is associated with facial height, nasal cavity width, interorbital distance and midfacial prognathism. The isolated cleft lip (CL) and combined cleft lip and palate (CLP) groups did not differ significantly from one another (Procrustes distance = 0.0416, p = 0.50). Procrustes distance permutation tests within the CL/P group showed a significant shape difference between unilateral clefts and bilateral clefts (Procrustes distance = 0.0728, p = 0.0001). Our findings indicate the morphological variation is similar to those of studies of CL/P patients and their unaffected close relatives in non-African populations., Conclusion: The mean facial shape in African children with non-syndromic CL/P differs significantly from children without orofacial clefts. The main differences involve interorbital width, facial width and midface prognathism. The axes of facial shape differences we observed are similar to the patterns seen in Caucasian populations, despite apparent differences in cleft prevalence and cleft type distribution. Similar facial morphology in individuals with CL/P in African and Caucasian populations suggests a similar aetiology.

Background: Clefts of the lip (CL), the palate (CP), or both (CLP) are the most common orofacial congenital malformations found among live births, accounting for 65% of all head and neck anomalies. The frequency and pattern of orofacial clefts in different parts of the world and among different human groups varies widely. Generally, populations of Asian or Native American origin have the highest prevalence, while Caucasian populations show intermediate prevalence and African populations the lowest. To date, little is known regarding the epidemiology and pattern of orofacial clefts in Tanzania., Methods: A retrospective descriptive study was conducted at Bugando Medical Centre to identify all children with orofacial clefts that attended or were treated during a period of five years. Cleft lip and/or palate records were obtained from patient files in the Hospital's Departments of Surgery, Paediatrics and medical records. Age at presentation, sex, region of origin, type and laterality of the cleft were recorded. In addition, presence of associated congenital anomalies or syndromes was recorded., Results: A total of 240 orofacial cleft cases were seen during this period. Isolated cleft lip was the most common cleft type followed closely by cleft lip and palate (CLP). This is a departure from the pattern of clefting reported for Caucasian and Asian populations, where CLP or isolated cleft palate is the most common type. The distribution of clefts by side showed a statistically significant preponderance of the left side (43.7%) (χ2 = 92.4, p < 0.001), followed by the right (28.8%) and bilateral sides (18.3%). Patients with isolated cleft palate presented at very early age (mean age 1.00 years, SE 0.56). Associated congenital anomalies were observed in 2.8% of all patients with orofacial clefts, and included neural tube defects, Talipes and persistent ductus arteriosus., Conclusions: Unilateral orofacial clefts were significantly more common than bilateral clefts; with the left side being the most common affected side. Most of the other findings did not show marked differences with orofacial cleft distributions in other African populations.