title: A new tool in birth defects research: the MZ half-sib model and its extension to grandchildren of identical twins.
mesh_terms: D000013:Congenital Abnormalities / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008431:Maternal-Fetal Exchange; D008433:Mathematics; D008954:Models, Biological; D010375:Pedigree; D011247:Pregnancy; D014427:Twins; D014430:Twins, Monozygotic