Biology 1001A Lecture Notes - Lecture 17: Genomic Imprinting, Sexual Conflict, Methyl Group
Document Summary
Hamiton"s rule: many examples of apparent altruism are not actually altruism at all, actions do not decrease fitness, even though they appear to. Their indirect fitness covers the cost to the organism"s direct fitness. Parent-orrspring conflict: within mammals, genetic conflict occurs within developing embryo/parent provide. Embryo wants more resources than mother is able to. Embryo is more related to itself than any subsequent offspring the parent will have. In a monogamous system, sexual conflict will not be as intense, as any future offspring would share half of alleles with current offspring. In promiscuous system, sexual conflict will be more intense, as future offspring will only be half-siblings. Parental conflict and genomic imprinting: ~1% of genes in mammals have only one allele expressed (either maternal or paternal) Methyl group gets attached to allele to silence a particular allele. Alleles from mother vs. father have different genetic interests female: most mammals are promiscuous: female"s future offspring will probably have a different father.