BIO 325 1st Edition Lecture 3Outline of Last Lecture I. Simple ProbabilityII. Mendelian GeneticsOutline of Current LectureI. Mendelian genetics in humansII. Departure from Mendelian geneticsa. But alleles still follow the basic Mendelian rulesCurrent LectureI. Gene behaviora. Not always clearly dominant/recessiveb. More than two kinds of alleles can be present for one genec. One gene can control more than one traitII. Mendelian inheritance in humansa. Use of pedigreesb. Most diseases caused by single genes are recessivei. Ex: colorblindness, albinism, cystic fibrosisc. Dominant diseasesi. Ex: adermatoglyphia, polydactyly, Huntington’s diseased. Carriers: Heterozygous for a certain diseaseIII. Pedigreesa. Pedigree for a recessive diseasei. Occurs rarely unless consanguineousii. Assume all other individuals are homozygous normal unless there is evidence to say clearly otherwiseiii. All of the children of 2 affected parents should be affectediv. Rare recessive traits show a horizontal pattern of inheritance1. Can be vertical if the trait is extremely common in the populationb. Pedigree for a dominant allelei. Diseased individual is assumed to be heterozygous unless every child has the diseaseii. Affected children always have at least one affected parentThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.iii. Show a vertical pattern of inheritanceIV. Incomplete Dominancea. Neither allele is dominant or recessiveb. Both contribute to the phenotype of the F1c. Heterozygous looks different from either homozygous (dominant or recessive) parentd. Each genotype has its own phenotypei. Phenotypic ratio=genotypic ratio=1:2:1e. Ex: Flower color (RR red Rr pink rr white)V. Codominancea. Ex: Human blood typesb. Both of the parental phenotypes are seen in the F1 hybridMendel’s laws still hold in both incomplete dominance and codominance. c. Genes may have more than two alleles (ex: blood type- I^A, I^B, i)d. Dominance series e. Pleiotropy- One gene may control multiple phenotypes; multiple phenotypes will segregate togetheri. Recessive-lethal alleleii. Sickle-cell anemia causes multiple physical