While working in a pathology lab, you are presented with an ovine blood sample (2n=54) that is suspected to have a genetic abnormality. You decide to karyotype the sample and diagnose trisomy 24.
1. Assume two hypothetical genes A and B are located on chromosomes 24 and 25 respectively. How many alleles for each gene will be present in the Primary oocyte, secondary oocyte and ovum that produced the animal with the abnormal karyotype indicated above â Provide answers for all possible scenarios.
2. Describe the number of autosomal chromosomes and chromatids in the Primary oocyte, Secondary oocyte and ovum that produced the animal with the abnormal karyotype indicated above â Provide answers for all possible scenarios
3. Another two hypothetical genes P and Q are located on chromosome 1; with the dominant alleles (P and Q) in coupling phase, and recessive alleles (p and q) in coupling phase on homologous chromosomes. Suppose a single crossing over occurs between the two genes during meiosis. What is the probability that the ovum that gave rise to karyotypically abnormal animal contains a chromatid with dominant alleles P and Q in coupling phase?
4. Suppose the animal had an XXY karyotype instead of trisomy 24. Did non-disjunction occur in the male or female parent (or both) and at which division(s), meiosis I or meiosis II?
While working in a pathology lab, you are presented with an ovine blood sample (2n=54) that is suspected to have a genetic abnormality. You decide to karyotype the sample and diagnose trisomy 24.
1. Assume two hypothetical genes A and B are located on chromosomes 24 and 25 respectively. How many alleles for each gene will be present in the Primary oocyte, secondary oocyte and ovum that produced the animal with the abnormal karyotype indicated above â Provide answers for all possible scenarios.
2. Describe the number of autosomal chromosomes and chromatids in the Primary oocyte, Secondary oocyte and ovum that produced the animal with the abnormal karyotype indicated above â Provide answers for all possible scenarios
3. Another two hypothetical genes P and Q are located on chromosome 1; with the dominant alleles (P and Q) in coupling phase, and recessive alleles (p and q) in coupling phase on homologous chromosomes. Suppose a single crossing over occurs between the two genes during meiosis. What is the probability that the ovum that gave rise to karyotypically abnormal animal contains a chromatid with dominant alleles P and Q in coupling phase?
4. Suppose the animal had an XXY karyotype instead of trisomy 24. Did non-disjunction occur in the male or female parent (or both) and at which division(s), meiosis I or meiosis II?
