Abstract
Li-Fraumeni syndrome is an inherited disorder and leads to the presentation of various types of cancer in a family. This experiment was conducted to determine first, based on Valerie’s family pedigree, if Li-Fraumeni syndrome is present in her family and who has been affected by it. Once this was established, gel electrophoresis was used to compare samples of Valerie’s blood and normal breast tissue to her tumor tissue and to a wild type DNA fragment to see whether or not her cancer has metastasized; it did not appear that this was the case. Lastly, her children’s p53 gene was sequenced and compared to the wild type p53 sequence to determine whether any of them carried the mutation. Two of her children do have the mutation at two points …show more content…
Additionally, cancer cells can ignore signals from the body that stop cell growth and that cause programmed cell death.1 There are many factors that play a role in a cancer diagnosis. These include the environment and personal habits, such as nutrition or smoking. Several forms of cancer have familial pre-disposition, which appear to be linked to an inherited mutation in suppressor genes such as the p53 gene. According to the American Cancer society, tumor suppressor genes are normal genes that slow down cell division, repair DNA, and mark cells for cell death.2 When these genes are mutated, cell growth is no longer regulated, leading to the possibility of developing cancer. Inherited abnormalities of tumor suppressor genes have been found in some family cancer syndromes and cause certain types of cancer to run in families.2 The p53 gene, which codes for the p53 protein that regulates the cell cycle, has been found in more than half of human cancers.2 This gene is frequently inactivated in a variety of cancers, including leukemias, lymphomas, sarcomas, brain tumors, and carcinomas.3 In this lab experiment, a woman named Valerie is suspected of having …show more content…
In Li-Fraumeni, notable markers of the syndrome can be seen in a family pedigree, which, as stated in the introduction, are multiple individuals within a family with various types of cancer and early disease onset. Li-Fraumeni syndrome is rare, but, when present, affects young members of the family and results in a high mortality rate.4 Valerie’s family pedigree strongly suggests that Li-Fraumeni syndrome is present. As a second method of analysis, various samples of Valerie’s DNA were run to determine if her cancer has spread. There were five samples in the gel, three of which were from Valerie, with the other two were used as a method of comparison. The DNA ladder is simply used to determine fragment lengths. The control, however, is very important in the determination of possible metastases because it contains wild type (normal) DNA that can be compared to Valerie’s DNA samples. In Valerie’s peripheral blood and normal breast tissue samples, a copy of the wild type DNA is present in addition to a copy of the cancer DNA, thus she is heterozygous in this area. In Valerie’s tumor tissue sample, however, there is no copy of the normal gene present, thus she is homozygous for the cancer DNA in this area. Because Valerie has one copy of the wild type
Li-Fraumeni syndrome is an inherited disorder and leads to the presentation of various types of cancer in a family. This experiment was conducted to determine first, based on Valerie’s family pedigree, if Li-Fraumeni syndrome is present in her family and who has been affected by it. Once this was established, gel electrophoresis was used to compare samples of Valerie’s blood and normal breast tissue to her tumor tissue and to a wild type DNA fragment to see whether or not her cancer has metastasized; it did not appear that this was the case. Lastly, her children’s p53 gene was sequenced and compared to the wild type p53 sequence to determine whether any of them carried the mutation. Two of her children do have the mutation at two points …show more content…
Additionally, cancer cells can ignore signals from the body that stop cell growth and that cause programmed cell death.1 There are many factors that play a role in a cancer diagnosis. These include the environment and personal habits, such as nutrition or smoking. Several forms of cancer have familial pre-disposition, which appear to be linked to an inherited mutation in suppressor genes such as the p53 gene. According to the American Cancer society, tumor suppressor genes are normal genes that slow down cell division, repair DNA, and mark cells for cell death.2 When these genes are mutated, cell growth is no longer regulated, leading to the possibility of developing cancer. Inherited abnormalities of tumor suppressor genes have been found in some family cancer syndromes and cause certain types of cancer to run in families.2 The p53 gene, which codes for the p53 protein that regulates the cell cycle, has been found in more than half of human cancers.2 This gene is frequently inactivated in a variety of cancers, including leukemias, lymphomas, sarcomas, brain tumors, and carcinomas.3 In this lab experiment, a woman named Valerie is suspected of having …show more content…
In Li-Fraumeni, notable markers of the syndrome can be seen in a family pedigree, which, as stated in the introduction, are multiple individuals within a family with various types of cancer and early disease onset. Li-Fraumeni syndrome is rare, but, when present, affects young members of the family and results in a high mortality rate.4 Valerie’s family pedigree strongly suggests that Li-Fraumeni syndrome is present. As a second method of analysis, various samples of Valerie’s DNA were run to determine if her cancer has spread. There were five samples in the gel, three of which were from Valerie, with the other two were used as a method of comparison. The DNA ladder is simply used to determine fragment lengths. The control, however, is very important in the determination of possible metastases because it contains wild type (normal) DNA that can be compared to Valerie’s DNA samples. In Valerie’s peripheral blood and normal breast tissue samples, a copy of the wild type DNA is present in addition to a copy of the cancer DNA, thus she is heterozygous in this area. In Valerie’s tumor tissue sample, however, there is no copy of the normal gene present, thus she is homozygous for the cancer DNA in this area. Because Valerie has one copy of the wild type