Allele specific oligonucleotides (ASO) can be used to determine the different alleles present in a DNA sample. Single sperm, which have completed meiosis, can be used for a polymerase chain reaction (PCR). The amplified DNA is then spotted to filters and hybridized with probes that recognize single nucleotide differences. A sperm sample was collected from a single individual and DNA was extracted from individual sperm. For each DNA sample, four different regions of the genome were amplified using PCR (called A, B, D, and E). For each DNA sample, ASO probes were used to determine the allele present (Either allele 1 or 2) for each region of the genome amplified. X indicates the allele is present and - indicates the allele is not present.
Number of Sperm Loci and Alleles
A1 A2 B1 B2 D1 D2 E1 E2
45 X - X - X - - X
46 - X X - - X X -
7 X - X - X - X -
8 - X X - - X - X
17 X - X - - X - X
19 - X X - X - X -
(Notice that there are only six classes of genotypes among the products of meiosis. For three segregating genes, you would expect to see eight different genotypic combinations. The missing genotypes are the DCO combinations and thus you should figure out what combinations are missing and assign them a value of zero)
What is an estimate of the map distance for each pair of genes?
(for unlinked gene pairs enter 50 and round off your answer to one significant digit to the right of the decimal point, i.e. 12.8 mu. If can't determine linkage, enter "-1")
A-D distance?
D-E distance?