Three genes in the lab bug an insect specially bred for gene

Three genes in the lab bug, an insect specially bred for genetics problems, are linked as indicated in the following gene map:

                        -----------------A/a------10 cM-----B/b------------------25 cM-------------------C/c------

Parental AAbbCC and aaBBcc lab bugs are mated to yield an AaBbCc F₁ generation. The F₁ individuals are then test-crossed with aabbcc lab bugs. Assuming that 1,000 test-cross offspring (the lab bug is very prolific) hatch, predict the number of test-cross offspring exhibiting non-recombinant and recombinant phenotypes. (For simplicity, ignore the possibility of double crossover offspring.)

                        Type of

Genotype         Crossover                     # Offspring

AabbCc            Non-recombinant                

aaBbcc             Non-recombinant                

Aabbcc            Recombinant                       

aaBbCc            Recombinant                       

AaBbcc            Recombinant                       

aabbCc             Recombinant                       

(HINT: Look at the parental generation to see which alleles are linked together.)

**Please write in detail so I can learn from it! Thank you!!

Solution

Answer:

Genotype         Crossover                     # Offspring

AabbCc            Non-recombinant 325

aaBbcc             Non-recombinant 325

Aabbcc            Recombinant 125

aaBbCc            Recombinant 125

AaBbcc            Recombinant 50

aabbCc             Recombinant 50

Explanation:

Linked gene configuration= AbC/aBc

Map distance = recombination frequency

Single cross over b/w a & b produces the following progeny in 10/100 * 1000 = 100

ABc/abc = 50

abC/abc=50

Single cross over b/w b & c produces the following progeny in 25/100 * 1000 = 250

Abc/abc= 125

aBC/abc=125

Total recombinants = 100 + 250 = 350

Non-recombinants = 1000-350 = 650

AabbCc=325          

aaBbcc=325