In grapes, the wild-type DND1 gene confers resistance to attain viruses, and strains are susceptible to viruses. The EDS1 gene confers resistance to powdery mildew, a type of fungal infection. The genes are linked, eight map units apart on chromosome 17. A third gene, IR 1. imparts resistance to certain lepidopteran leafminers and is 10 map units from EDS1 and 18 map units from UNDI The abserved double crossover rate is 0.3%. What is the interference? a. 37.5%
b. 25.%
c. 62.5%
d. 75%

I = 62.5%

Explanation:

Available data:

the wild-type DND1 gene confers resistance to attain viruses. Strains are susceptible to virusesThe EDS1 gene confers resistance to powdery mildew, a type of fungal infection The genes are linked, eight map units apart on chromosomeA third gene, IR 1. imparts resistance to certain lepidopteran leafminers and is 10 map units from EDS1 and 18 map units from DNDIThe observed double crossover rate is 0.3%

According to this information, we can picture the position of each gene in the chromosome

---DND1EDS1IR1---

       ║ 8MU║10MU║

       ║18MU║

The map unit is the distance between the pair of genes for which one of every 100 meiotic products results in a recombinant product.

1% of recombinations = 1 map unit = 1cM. The maximum recombination frequency is always 50%.

So, if we know the distances between genes, we know their recombination percentages.

DND1-EDS1 = 8 MU = 8% recombinationEDSI-IR1 = 10 MU = 10% recombination

To calculate interference, first, we need to know the coefficient of coincidence, CC.    

CC= observed double recombinant frequency/expected double recombinant frequency

Note:

observed double recombinant frequency=total number of observed double recombinant individuals/total number of individuals expected double recombinant frequency: recombination frequency in region I x recombination frequency in region II.

CC= (0.003)/(0.08 x 0.1)

CC=0.003/0.008

CC=0.375

CC = 37.5%

The coefficient of interference, I, is complementary with CC.

I = 1 - CC

I = 1 - 0.375

I = 0.625

I = 62.5%

   

Explanation:u pretty on moms