Background

Development of the face is dependent on complex interactions of genetic and environmental factors, and is also affected by maternally derived exposures. Alcohol consumption in pregnancy is an important health issue and the DOH currently advise that pregnant women or women trying to conceive should avoid drinking alcohol1.Prenatal alcohol exposure causes a continuum of effectsand is thought to be a leading cause of learning disability in the western world with between 0.2 and 2.0 cases per 1,000 live births. Some of the highest incidence levels have been identified in Eastern Europe, in indigeneous North American communities, and in the South African Cape-Coloured population.The most severe phenotype, fetal alcohol syndrome (FAS), affects face shape, growth and neurobehavior. Fetal alcohol spectrum disorders (FASD) include FAS and other pathologies arising from prenatal alcohol exposure.

The characteristic facial features believed to be due to alcohol ingestion between 10 and 20 wks of gestation include smooth philtrum, thin upper lip vermilion, long upper lip, shortened palpebral aperture width, flattened mid-face and small head circumference. The timing of maternal alcohol consumption is considered to affect the severity of facial dysmorphology and through PH's involvement in the CIFASD consortium (www.CIFASD.com), we recently reported on the link between neurofacial effects and timing of ethanol exposure in a mouse model2. In another CIFASD study, of South African children3, we used face shape to induce classification schemes and tested agreement with clinical FASD categorization: FAS, partial FAS, and HE (heavily alcohol exposed without clinically detectable facial features). The more heterogeneous phenotype of HE forced us to introduce a novel clustering technique, signature graph analysis4, which normalizes face shape and links individuals with similar facial dysmorphism. Signature graph analysis identified half of the HE group as having facial dysmorphism more FAS-like than control-like. These HE individuals performed less well on psychometric tests than HE individuals who facially were more control-like. We also demonstrated that heat map comparisons of, and animated morphs between, individual faces and matched control means revealed facial dysmorphism otherwise overlooked. Thus, visualizations and signature analysis can help pediatricians detect facial dysmorphism across the fetal alcohol spectrum, especially in non-syndromal alcohol exposed cases.

The ALSPAC database provides an opportunity for a much larger-scale investigation of associations between volume and timing of maternal alcohol consumption during pregnancy and facial dysmorphism. In addition, we wish to explore further associations between facial characteristics, cognitive impairment and psychosis

Subjects and data

There are 4747 3D facial scans captured for the 15 year old cohort and these images provide detailed facial morphology at tens of thousands of 3D surface points. The 3D scans have been landmarked and derived facial features recorded. ALSPAC has also collected information on maternal alcohol consumption through questionnaires at 12, 18 and 32 weeks of gestation as well as data regarding the drinking consumption of the parents. In addition, quantity of maternal alcohol intake data is available related to the timing of fetal development: before pregnancy, first trimester of pregnancy, and at around the time the baby was first felt to move. The dataset identified above will need to be extracted and sent to both Peter Hammond and Stephen Richmond.