Question

Two genes ‘d’ and ‘t’ are assumed to show linkage as well as produce recombinants upto 30%. If dd/ dd individual is crossed with one which is tt/tt. What genotype will produce in first filial generation? Also give the possible meiotic products produced by first generation. If a test cross is performed what phenotypes and genotypes will produced in progeny.   

Answer 1

The genotype produced in first filial generation when dd and tt crosses is dt heterozygous .The meiotic products produced in the first generation are 2d sister homologous chromosomes and 2s sisters homologous chromosomes.

1. dd-homozygous dominant (genotype) - Normal (Phenotype)
2. 2dt-heterozygous (genotype) - Carrier (Phenotype)
3. tt- homologous recessive (genotype) -contains symptoms