ChloeYeo
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In a dihybrid cross of two autosomally linked genes, why is it that the higher proportion of the F2 offspring inherits their parents' (F1 offspring) genotype and phenotype?

Is it because the two autosomally linked genes are inherited together, or is it because the phenotypic ration for F2 generation is that expected for the F2 generation of a monohyprid cross which is 3:1?

Either way I still don't fully understand why that means a higher proportion of F2 offspring will be heterozygous.

Can anyone please explain in detail?

Thank you so much!!
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ChloeYeo
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(Original post by ChloeYeo)
In a dihybrid cross of two autosomally linked genes, why is it that the higher proportion of the F2 offspring inherits their parents' (F1 offspring) genotype and phenotype?

Is it because the two autosomally linked genes are inherited together, or is it because the phenotypic ration for F2 generation is that expected for the F2 generation of a monohyprid cross which is 3:1?

Either way I still don't fully understand why that means a higher proportion of F2 offspring will be heterozygous.

Can anyone please explain in detail?

Thank you so much!!
OHH because

as the phenotypic ratio in the F2 generation of a dihybrid cross involving two autosomally linked genes is that expected for the F2 generation of a monohybrid cross which is 3:1,

for normal dihybrid cross, in the F2 generation, 4/16 i.e. 1/4 is heterozygous (which is the same as the parents'/F1 offspring's genotype which is all heterozygous.)
for a normal monohybrid cross, 2/4 i.e. 1/2 of the F2 generation is heterozygous.

1/2 > 1/4
so if there is autosomal linkage(in a dihybrid cross), a higher proportion of the F2 offspring will be heterozygous/ will inherit their parents' heterozygous genotype and phenotype.
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