In a study of a certain plant species, researchers have identified two genes, G and H, located on the same chromosome. A dihybrid plant that is heterozygous for both genes (GgHh) is crossed with a homozygous recessive plant (gghh). The following offspring were obtained:

250 GgHh
50 ggHh
50 Gghh
250 gghh
Using this information, which of the following gives the correct genetic map?

Consider the following DNA sequences:

Nucleotide position
                   1       5       10
Person 1 ...GCCTGCCTGA...
Person 2 ...GCCAGCCTTA...
Person 3 ...GCCGGCCTCA...
Person 4 ...GCCCGCCTAA...

What is the nucleotide position of all the SNPs in the given sequences?

Marfan Syndrome is a rare autosomal dominant condition affecting 1 in 5000 individuals, caused by a mutation in a gene called FBN1. Mapping the FBN1 gene on chromosome 15 requires genetic linkage studies to test the segregation of FBN1 gene and DNA genetic markers on different chromosomes. A DNA marker comprising of two alleles denoted as 1 and 2, is linked to FBN1. The pedigree diagram given below gives the genotype of each family member.

Which of the following options gives the correct estimate of the recombination frequency of DNA markers among offspring?

The following diagram shows the genetic map of four linked genes on a chromosome. 

What will be the distance between D and B? 

The genetic distances between the three genes (genes AB, CD, and EF) were identified using a two-point mapping cross. Given the following distances, what is the sequence of the three genes in the chromosome?

 AB-EF: 39 mu
 AB-CD: 5 mu
 CD-EF: 34 mu

The purple gene in Drosophila specifies the normal and red eyes (for the dominant pr+ allele) and purple eyes ( for the recessive pr allele). Another gene called the vestigial gene specifies normal, long wings (for dominant vg+ allele) and short wings (for recessive vg allele). A double heterozygous female mates with a tester (homozygous recessive for both genes) and yields the following offspring:

     pr+ vg+ and pr vg: 1422
     pr vg and pr vg: 1032
     pr+ vg and pr vg: 134
     pr vg+ and pr vg: 139

What is the recombination frequency between the purple and vestigial genes?

The following image shows the location of genes X, Y, and Z in a chromosome. If the distance between genes Y and Z is 10 mu and the distance between genes X and Y is 30 mu, what is the distance between genes X and Z?