Scientists have been studying the effects of Starkagaren Disease, which is regulated by the stgn gene, in cultured normal and breast cancer cell lines. They have fused a yellow fluorescent probe to the end of the stgn gene to study the disease more closely. By adding a probe, it will create a hybrid protein that emits a yellow color under a blue laser. This hybrid protein is known as a fluorescentâtagged protein, meaning that the protein itself will function and fold normally but it will be tagged with a yellow fluorescent probe (YFP) at the end. This allows the scientists to follow the protein through the cell cycle. They find that the stgn protein normally binds to centromeres in normal cells. After looking at cells at various stages of the cell cycle, they find that compared to normal cells, the breast cancer cells that express the Starkagaren Disease display abnormal nuclei, some appear very large, some have tiny nuclei, and some cells do not have a nucleus at all.
Scientists have figured out that Starkagaren Disease is passed on through a mutation in the germ cells. The mutation is found on the chromosome 12 so either the mother or father can pass on the gene. But in order for the disease to express, both parents need to have the mutation. You are a genetic counselor talking to two individuals that have familial history of either a grandparent or aunt or uncle with the disease, they would like you to explain their chances of having a child that could possible inherit the disease.
a) Would the defect be found in homologous chromosomes or sister chromatids, or both? Explain.
b) If the location of the gene with the defect is found near the tip of the chromosome, how likely would that defect transfer to a homologous chromosome? Explain how it may or may no occur.
Scientists have been studying the effects of Starkagaren Disease, which is regulated by the stgn gene, in cultured normal and breast cancer cell lines. They have fused a yellow fluorescent probe to the end of the stgn gene to study the disease more closely. By adding a probe, it will create a hybrid protein that emits a yellow color under a blue laser. This hybrid protein is known as a fluorescentâtagged protein, meaning that the protein itself will function and fold normally but it will be tagged with a yellow fluorescent probe (YFP) at the end. This allows the scientists to follow the protein through the cell cycle. They find that the stgn protein normally binds to centromeres in normal cells. After looking at cells at various stages of the cell cycle, they find that compared to normal cells, the breast cancer cells that express the Starkagaren Disease display abnormal nuclei, some appear very large, some have tiny nuclei, and some cells do not have a nucleus at all.
Scientists have figured out that Starkagaren Disease is passed on through a mutation in the germ cells. The mutation is found on the chromosome 12 so either the mother or father can pass on the gene. But in order for the disease to express, both parents need to have the mutation. You are a genetic counselor talking to two individuals that have familial history of either a grandparent or aunt or uncle with the disease, they would like you to explain their chances of having a child that could possible inherit the disease.
a) Would the defect be found in homologous chromosomes or sister chromatids, or both? Explain.
b) If the location of the gene with the defect is found near the tip of the chromosome, how likely would that defect transfer to a homologous chromosome? Explain how it may or may no occur.