What makes the difference between genetic linkage and association studies? Simply speaking, for linkage you need to inherit a particular marker allele from your parents where it does not matter if a child in another family inherits another allele (pending it shares it with its affected sibling). With association studies this matters.<\/p>\n
As we found with the much relaxed linkage strategy so many minor diverse loci, I assume a rather heterogeneous origin of complex diseases. There is no doubt about the importance of genes, but about the sharing of the same<\/strong> genetic abnormality. An (anonymous) position paper on basic Asthma Research Strategy II in Clin Exp All 2006; 36: 1326 says<\/p>\n \nThe average size of effect on asthma and related traits from common SNPs is small. For instance, seven common SNPs in the IL13 gene jointly accounted for only 0,5% of the variance of total IgE … With a heritability of circa 60% for total IgE this implies that hundreds of genes, each with small effects, may be involved in IgE regulation.\n<\/p><\/blockquote>\n Families presenting with a complex system disease will all have unique patterns how they arrive at the same clinical endpoint. Alpha-delta-gamma asthma, theta-kappa-jota schizophrenia or $%&# diabetes – are they combining lets say 3000 variations in 300 genes of 30 metabolic-signalling pathways to 1 disease of variable onset, severity and prognosis? Yea, yea.<\/p>\n\n <\/p>\n What makes the difference between genetic linkage and association studies? Simply speaking, for linkage you need to inherit a particular marker allele from your parents where it does not matter if a child in another family inherits another allele (pending it shares it with its affected sibling). With association studies this matters. As we found … Continue reading What could have been learned from linkage studies<\/span>