HMB265H1 Chapter Notes - Chapter 6: Hh Blood Group, Epistasis, Summer Squash

• School: UTSG
• Department: Human Biology
• Course: HMB265H1
• Professor: Maria Papaconstantinou

Document Summary

Hartwell et al. , 1st can. edition, chapter 2 (emphasis on pages 42-51) and chapter 8 (emphasis on pages 253-255) Most traits are regulated by two or more genes. Two genes can interact to determine one trait. 9 brown: 3 tan: 1 grey: 1 green. Four colour phenotypes arise from four genotypic classes, with each class defined in terms of presence or absence of dominant alleles. At least one dominant allele for each gene is necessary for the development of purple color. Complementary gene action: it talks two enzyme catalyzing two reaction. Only a-n- active both enzymes generate coloured. A-bb, aab-, aabb do not have functional form or enzyme. Coat color depends on allelic combination of two independently assorting genes. E no effect, ee gold because it hides the effect of brown/black. Epistasis: a gene interaction in which the effects of an allele at one gene hide the effect of alleles at another gene.