WHETHER MOM OR DAD was responsible for a patient's blue eyes may not matter, but the identity of the parent who passed on a defective gene may drastically affect the course of the resultant disease.
That was the word from investigators who reported on the effects of genetic imprinting at the recent annual short course in medical and mammalian genetics in Bar Harbor, Maine. The course was sponsored by Johns Hopkins University in Baltimore, Md, and the Jackson Laboratory in Bar Harbor.
Genetic imprinting is defined as "the differential modification of parental contributions to the zygote, resulting in differential expression of information inherited from those parents." In other words, a gene inherited from the mother may be expressed differently from an identical gene inherited from the father.
The imprinting paradigm is providing an explanation for many heretofore unexplained phenomena seen in both laboratory experiments and in clinical genetics. Said Judith