title: The epidemiology of neural tube defects. A mathematical model.
abstract: The incidence of neural tube defects (NTDs) shows a seasonal variation; and incidence as well as female/male ratio show a relation with latitude. The interrelation of these phenomena is presented as a mathematical model, which has a 'predictive' value, and is an instrument in estimating the local gene frequency. The model offers a simple explanation of the conundrum why the double X-chromosome has a variable influence on the sex ratio. UV light and the herpes virus fit in this model as related causative factors of NTDs.
authors.forename: F J
authors.initials: FJ
authors.lastname: Van Rootselaar
mesh_terms: D015981:Epidemiologic Factors; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008433:Mathematics; D008954:Models, Biological; D009436:Neural Tube Defects / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics; D012621:Seasons; D012737:Sex Factors; D014466:Ultraviolet Rays / Q000009:adverse effects