Answer 4. a) Mating X is informative. It contains all different alleles. So, different gametes will be formed. If the progeny contains same genotypes as the parental genotype, then it means that linkage is there. On the other hand, mating W, Y and Z are having homozygous genotypes. They will form same gametes. So, it will be impossible to identify whether recombination has occurred or not. b) Locus \'A\' and \'B\' both are SNPs. It is important to note that SSRs (short sequence repeats) are highly polymorphic loci; and have up to 20 alleles. But here only 4-5 alleles are there. So, it is SNP, not SSR. c) Yes, if the parents were homozygous at both loci, then it would be extremely easy to trace the gametes, which have come from each parent. d) 20 out of 40 are recombinants. So, 50% are recombinants, and the rest 50% are linked. So, the distance between A and B = 50mu. If distance between two loci increase, cross over frequency also increases. This means that linkage occurs when distance between two loci is small. Ideally linkage occurs when distance between two loci is less than 50mu. So, the above two loci are not linked. Solution Answer 4. a) Mating X is informative. It contains all different alleles. So, different gametes will be formed. If the progeny contains same genotypes as the parental genotype, then it means that linkage is there. On the other hand, mating W, Y and Z are having homozygous genotypes. They will form same gametes. So, it will be impossible to identify whether recombination has occurred or not. b) Locus \'A\' and \'B\' both are SNPs. It is important to note that SSRs (short sequence repeats) are highly polymorphic loci; and have up to 20 alleles. But here only 4-5 alleles are there. So, it is SNP, not SSR. c) Yes, if the parents were homozygous at both loci, then it would be extremely easy to trace the gametes, which have come from each parent. d) 20 out of 40 are recombinants. So, 50% are recombinants, and the rest 50% are linked. So, the distance between A and B = 50mu. If distance between two loci increase, cross over frequency also increases. This means that linkage occurs when distance between two loci is small. Ideally linkage occurs when distance between two loci is less than 50mu. So, the above two loci are not linked..

1. Answer 4.
a) Mating X is informative. It contains all different alleles. So, different gametes will be formed.
If the progeny contains same genotypes as the parental genotype, then it means that linkage is
there.
On the other hand, mating W, Y and Z are having homozygous genotypes. They will form same
gametes. So, it will be impossible to identify whether recombination has occurred or not.
b) Locus 'A' and 'B' both are SNPs. It is important to note that SSRs (short sequence repeats)
are highly polymorphic loci; and have up to 20 alleles. But here only 4-5 alleles are there. So, it
is SNP, not SSR.
c) Yes, if the parents were homozygous at both loci, then it would be extremely easy to trace the
gametes, which have come from each parent.
d) 20 out of 40 are recombinants. So, 50% are recombinants, and the rest 50% are linked. So, the
distance between A and B = 50mu.
If distance between two loci increase, cross over frequency also increases. This means that
linkage occurs when distance between two loci is small. Ideally linkage occurs when distance
between two loci is less than 50mu.
So, the above two loci are not linked.
Solution
Answer 4.
a) Mating X is informative. It contains all different alleles. So, different gametes will be formed.
If the progeny contains same genotypes as the parental genotype, then it means that linkage is
there.
On the other hand, mating W, Y and Z are having homozygous genotypes. They will form same
gametes. So, it will be impossible to identify whether recombination has occurred or not.
b) Locus 'A' and 'B' both are SNPs. It is important to note that SSRs (short sequence repeats)
are highly polymorphic loci; and have up to 20 alleles. But here only 4-5 alleles are there. So, it
is SNP, not SSR.
c) Yes, if the parents were homozygous at both loci, then it would be extremely easy to trace the
gametes, which have come from each parent.
d) 20 out of 40 are recombinants. So, 50% are recombinants, and the rest 50% are linked. So, the
distance between A and B = 50mu.
If distance between two loci increase, cross over frequency also increases. This means that
linkage occurs when distance between two loci is small. Ideally linkage occurs when distance

2. between two loci is less than 50mu.
So, the above two loci are not linked.