r.keen at umds.ac.uk wrote:
>I am interested in doing linkage in DZ twins, using them as age-
>matched sibs. Is anyone aware if the power of such anaysis would
>be similar to normal sibs, with particular reference to late-onset
>and age-related diseases. I should value opinions and any refernces.
For quantitative traits the age-matching will be an advantage. For
rare-ish disorders you'll probably get most power with pairs of
affected sibs rather than discordant sibs, so collecting affected sib
pairs might be better than collecting twins with only one guaranteed
affected. Pak Sham is about to embark on a big study of dizygotic
twins so you could email him: p.sham at ucl.ac.uk
Dave Curtis (dcurtis at hgmp.mrc.ac.uk)
Institute of Psychiatry, London
http://www.iop.bpmf.ac.uk/home/depts/psychmed/general/dcurtis/dcurtis.htm