a woman had a double recessive gene eye condition found in both men and women which was traced to her maternal grandfather. What will be the possible genotypes of her maternal grandmother?
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Could be any; homozygous recessive, homozygous dominant or heterozygous because it doesn't say whether or not the woman's mother had the condition. If she didn't, then it couldn't be homozygous recessive.
If homozygous recessive: then she would have had it too, as would her daughter (woman's mother).
If homozygous dominant: her daughter would have had one dominant allele and one recessive allele, meaning she would be a carrier, but not show the effects of the recessive allele (eye condition).
If heterozygous: she would be a carrier, meaning her daughter would either be homozygous recessive (50% chance) meaning she has the condition or also heterozygous (50% chance) meaning she's a carrier.
If you want, I can show the grids etc. as well?
If homozygous recessive: then she would have had it too, as would her daughter (woman's mother).
If homozygous dominant: her daughter would have had one dominant allele and one recessive allele, meaning she would be a carrier, but not show the effects of the recessive allele (eye condition).
If heterozygous: she would be a carrier, meaning her daughter would either be homozygous recessive (50% chance) meaning she has the condition or also heterozygous (50% chance) meaning she's a carrier.
If you want, I can show the grids etc. as well?