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How to figure out your genotype from your family tree... Do a pedigree chart. You need to create a family tree and label each box as to who it is. See diagram below. Males = . Females =. Grandmom. Grandpop. Grandpop. Grandmom. Mom. Dad. Brother. Brother/you. Sister/you. Sister.
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How to figure out your genotype from your family tree... Do a pedigree chart You need to create a family tree and label each box as to who it is. See diagram below. Males = Females = Grandmom Grandpop Grandpop Grandmom Mom Dad Brother Brother/you Sister/you Sister
Next, put in the alleles that are known. If the person shows the dominant trait, then put the dominant allele in the first spot. If the person shows the recessive trait, then put the recessive allele in both slots. Grandmom Grandpop Grandpop Grandmom _ _ _ _ _ _ _ _ _ _ _ _ Mom Dad _ _ _ _ _ _ _ _ Brother Brother/you Sister/you Sister
Let's use eye color. B=brown b=blue Known phenotypes: Mom = brown Grandmom (mom)= blue Grandpop (mom)= brown Dad = blue Grandmom (dad) = brown Grandpop (dad) = blue Me = Brown Sister = blue Put the letters where they belong Grandmom Grandpop Grandpop Grandmom _ _ _ _ _ _ _ _ B b _ _ _ _ Mom Dad _ _ _ _ _ _ _ _ Brother Brother/you Sister/you Sister
Let's use eye color. B=brown b=blue Known phenotypes: Mom = brown Grandmom (mom)= blue Grandpop (mom)= brown Dad = blue Grandmom (dad) = brown Grandpop (dad) = blue Me = Brown Sister = blue Put the letters where they belong Grandmom Grandpop Grandpop Grandmom This is what you know without using relationships to others. _ _ b _ _ b _ _ b B b _ _ B _ _ _ _ b b B Mom Dad Now fill in the letters due to relationships. _ _ b b _ _ _ _ _ _ B Brother Brother/you Sister/you Sister
Known phenotypes: Mom = brown Grandmom (mom)= blue Grandpop (mom)= brown Dad = blue Grandmom (dad) = brown Grandpop (dad) = blue Me = Brown Sister = blue Relationships: Grandpop (Mom) has brown eyes but no way to tell what the second allele may be. Grandmom (dad) has brown eyes but a blue eyed child. Second allele must be blue. Mom has brown eyes with a blue eyed parent as well as a blue eyed child. Second allele must be blue. I have brown eyes with a blue eyed parent. Second allele must be blue. b B B ? Grandmom Grandpop Grandpop Grandmom _ _ b _ _ ? b _ _ b B b _ _ B b _ _ _ _ b b b B Mom Dad _ _ b b _ _ _ _ B _ _ b Brother Brother/you Sister/you Sister