The question is how to fit a mode of inheritance given affection data in
a pedigree - this is called segregation analysis. A program I have used
to do this is called POINTER. It implements the mixed model of Morton
and Maclean, and can compare single gene to multifactorial hypotheses.
It can also provide best estimates for the transmission parameters of
the major locus. I expect if you contacted Newton Morton
(nmorton at uk.ac.crc or @crc.ac.uk) he could let you know where you might
obtain it. I gather he is in the process of updating it. (Actually,
pedigrees have to be broken down into nuclear families with "pointers".)
I believe one can also perform a segregation analysis with ILINK (from
the LINKAGE programs of Ott et al). I must confess I haven't done this
myself. Instead of iterating over map position the penetrance parameters
can be iterated to maximise the likelihood of the observed affection
pattern. The disadvantage would be that one cannot compare single locus
with multifactorial transmission, only get the best-fitting parameters
for the former.
Dave Curtis
Academic Department of Psychiatry, Janet: dcurtis at UK.AC.CRC
St. Mary's Hospital, Elsewhere: dcurtis at CRC.AC.UK
Praed Street, London W2. EARN/Bitnet: dcurtis%CRC at UKACRL
Tel 071-725 1993 Usenet: ...!mcsun!ukc!mrccrc!D.Curtis
