robison at lipid.harvard.edu
Tue Oct 18 23:24:20 EST 1994
Belinda J.F. Rossiter (rossiter at bcm.tmc.edu) wrote:
: In article <36q2ak$k7r at vixen.cso.uiuc.edu>, dstone at prairienet.org (David
: M. Stone) wrote:
: > I recently received a grant for a teacher update workshop.
: > I am interested in having a number of speakers present regarding
: > a number of topics. Can anyone tell me specifically which topics
: > fit under the "umbrella" of nontraditional inheritance?
The already mentioned trinucleotide repeat expansion concept is a good
one. It is nontraditional because the severity of the disease can increase
with each transmission of the disease allele. This is due to the
expansion of the unstable repeat (there is a pre-explanation term
for this phenomenon which escapes me).
Other candidates for "nontraditional inheritance"
1) Mitochondrial inheritance -- only from the mother in humans.
There are several genetic diseases associated with mitochondrial
genetic defects. Mitochondria are energy-producing organelles with
their own genome, and are inherited only from the mother in the
vast majority of cases.
Imprinting refers to a difference in a gene's effect dependent
on which parent it was inherited from.
In some cases, genetic
diseases occur in heterozygous individuals, because the locus
is imprinted and the individual has the bad luck to inherit
the functional copy from the parent whose contribution is turned off.
3) Uniparental disomy
In some rare cases, a karyotypically-normal individual inherits both
copies of a chromosome (or a large part of a chromosome) from the
I'm sure someone out there can supply more...
Department of Cellular and Developmental Biology
Department of Genetics / HHMI
robison at mito.harvard.edu
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