title: X-linkage: ascertainment through doubly ill probands.
mesh_terms: D001714:Bipolar Disorder / Q000235:genetics*; D003117:Color Vision Defects / Q000235:genetics; D005260:Female; D005808:Genes, Recessive; D008040:Genetic Linkage; D005821:Genetic Techniques; D006801:Humans; D008297:Male; D010375:Pedigree; D011336:Probability; D012729:Sex Chromosome Aberrations; D014960:X Chromosome