Pedigree analysis is a fundamental tool for investigating whether or not a trait is following a Mendelian pattern of inheritance. It can also be used to help identify individuals within a family who may be at risk for the trait. Adam and Sarah, a young couple of Eastern European Jewish ancestry, went to a genetic counselor because they were planning a family and wanted to know what their chances were for having a child with a genetic condition. The genetic counselor took a detailed family history from both of them and discovered several traits in their respective families. Sarah’s maternal family history is suggestive of an autosomal dominant pattern of cancer predisposition to breast and ovarian cancer because of the young ages at which her mother and grandmother were diagnosed with their cancers. If a mutant allele that predisposed to breast and ovarian cancer was inherited in Sarah’s family, she, her sister, and any of her own future children could be at risk for inheriting this mutation. The counselor told her that genetic testing is available that may help determine if this mutant allele is present in her family members. Adam’s paternal family history has a very strong pattern of early onset heart disease. An autosomal dominant condition known as familial hypercholesterolemia may be responsible for the large number of deaths from heart disease. As with hereditary breast and ovarian cancer, genetic testing is available to see if Adam carries the mutant allele. Testing will give the couple more information about the chances that their children could inherit this mutation. Adam had a first cousin who died from Tay-Sachs disease (TSD), a fatal autosomal recessive condition most commonly found in people of Eastern European Jewish descent. Because TSD is a recessively inherited disorder, both of his cousin’s parents must have been heterozygous carriers of the mutant allele. If that is the case, Adam’s father could be a carrier as well. If Adam’s father carries the mutant TSD allele, it is possible that Adam inherited this mutation. Because Sarah is also of Eastern European Jewish ancestry, she could also be a carrier of the gene, even though no one in her family has been affected with TSD. If Adam and Sarah are both carriers, each of their children would have a 25% chance of being afflicted with TSD. A simple blood test performed on both Sarah and Adam could determine whether they are carriers of this mutation. Would you want to know the results of the cancer, heart disease, and TSD tests if you were Sarah and Adam? Is it their responsibility as potential parents to gather this type of information before they decide to have a child?

Pedigree analysis is a fundamental tool for investigating whether or not a trait is following a Mendelian pattern of inheritance. It can also be used to help identify individuals within a family who may be at risk for the trait. Adam and Sarah, a young couple of Eastern European Jewish ancestry, went to a genetic counselor because they were planning a family and wanted to know what their chances were for having a child with a genetic condition. The genetic counselor took a detailed family history from both of them and discovered several traits in their respective families. Sarahs maternal family history is suggestive of an autosomal dominant pattern of cancer predisposition to breast and ovarian cancer because of the young ages at which her mother and grandmother were diagnosed with their cancers. If a mutant allele that predisposed to breast and ovarian cancer was inherited in Sarahs family, she, her sister, and any of her own future children could be at risk for inheriting this mutation. The counselor told her that genetic testing is available that may help determine if this mutant allele is present in her family members. Adams paternal family history has a very strong pattern of early onset heart disease. An autosomal dominant condition known as familial hypercholesterolemia may be responsible for the large number of deaths from heart disease. As with hereditary breast and ovarian cancer, genetic testing is available to see if Adam carries the mutant allele. Testing will give the couple more information about the chances that their children could inherit this mutation. Adam had a first cousin who died from Tay-Sachs disease (TSD), a fatal autosomal recessive condition most commonly found in people of Eastern European Jewish descent. Because TSD is a recessively inherited disorder, both of his cousins parents must have been heterozygous carriers of the mutant allele. If that is the case, Adams father could be a carrier as well. If Adams father carries the mutant TSD allele, it is possible that Adam inherited this mutation. Because Sarah is also of Eastern European Jewish ancestry, she could also be a carrier of the gene, even though no one in her family has been affected with TSD. If Adam and Sarah are both carriers, each of their children would have a 25% chance of being afflicted with TSD. A simple blood test performed on both Sarah and Adam could determine whether they are carriers of this mutation. Would you decide to have a child if the test results said that you carry the mutation for breast and ovarian cancer? The heart disease mutation? The TSD mutation? The heart disease and the mutant alleles?

Pedigree Analysis Is a Basic Method in Human Genetics Using the pedigree provided, answer the following questions. a. Is the proband male or female? b. Is the grandfather of the proband affected? c. How many siblings does the proband have, and where is he or she in the birth order?

A proband female with an unidentified disease seeks the advice of a genetic counselor before starting a family. Based on the following data, the counselor constructs a pedigree encompassing three generations: (1) The maternal grandfather of the proband has the disease. (2) The mother of the proband is unaffected and is the youngest of five children, the three oldest being male. (3) The proband has an affected older sister, but the youngest siblings are unaffected twins (boy and girl). (4) All the individuals who have the disease have been revealed. Duplicate the counselors feat

Phenylketonuria (PKU) is a human hereditary disease resulting from the inability of the body to process the chemical phenylalanine, which is contained in the protein we eat. PKU is manifest in early infancy and, if it remains untreated, generally leads to cognitive impairment. PKU is caused by a recessive allele with simple Mendelian inheritance. A couple intends to have children but consults a genetic counselor because the man has a sister with PKU and the woman has a brother with PKU. There are no other known cases in their families. They ask the genetic counselor to determine the probability that their first child will have PKU. What is this probability?

A woman knows that her mother is a carrier of Kartagener’s syndrome (an autosomal recessive disorder). The woman does not know if either she or her husband are carriers. The couple wants to have a child, but is worried about whether or not they could have a child with Kartagener’s syndrome. Should the couple seek the advice of a genetic counselor? In other words, is there a chance they could have an affected child? If there is a chance, please make sure your answer includes the specific parental genotypes necessary to make this possible.

In the previous topic, you learned that Gregor Mendel used Pisum sativum to conceptualize the governing laws of Genetics. In this activity, we will recall how Gregor Mendel utilized the idea of classical breeding to come up with desirable traits. Supposed you have two individual peas. One of the peas is a pure breed with round green seeds while the other has heterozygous round yellow seeds. Supposed a farmer wants to have pure breed peas that have green wrinkled seeds. How are you going to come up with these traits using the two peas that you have? (Note: If the F1 does not include a pure breed green wrinkled seed, you will use the F1 peas for next generation breeding and so on until you have the desired traits. Pure breed means homozygous alleles.) Show the Punnett squares for the cross. You will come up with two or more squares based on how many generations you made.

Lorenzo has a double row of eyelashes (MIM 126300) which he inherited from his mother as a dominant trait. His maternal grandfather is the only other relative to have it. Fatima, who has normal eyelashes, marries Lorenzo. The first child, Nicola (girl) has normal eyelashes. Now Fatima is pregnant again and hopes for a child with double eyelashes. What chance does the child have of inheriting double eyelashes? Draw a pedigree of this family.

Make a pedigree analysis on a five generation family using both maternal and paternal side. (great great grandparents as generation 1) All have a light brown skin color and straight hair. Use attached photo as a reference. (All names with highlighted yellow color are female. The rest are male. Name with red is deceased person. Name with green color are their spouse. Name with underline is the 5th gen (kids) )

Draw the following pedigree and identify the mode of inheritance (only identify by shading individuals who express the trait). Please provide the genotype for each individual. Remember if you cannot identify whether an individual is TT or Tt please use the T- annotation: The grandmother expresses the trait and the grandfather does not. The first daughter does not express the trait and marries a man who does not express the trait. The second daughter does not express the trait and marries a man who does not express the trait. The son of the first daughter and her husband expresses the trait. The second son of the first daughter and her husband does not express the trait. The second daughter and her husband have twin daughters that do not express the trait.

A newly described rare and potentially fatal condition causes heart rate to be unusually low in adults (between 30-45 beats per minute). A series of studies have shown a possible genetic link. Normal heart rate in adults is typically between 60 to 100 bpm. A family's medical chart that includes afflicted individuals is provided below. As a medical researcher, your supervisor asks you to produce a pedigree of this family to visualize and to determine a possible pattern of inheritance for this condition. As such, based on the data, draw the pedigree (clearly identifying who is afflicted and not afflicted) and your conclusion as to the mode of inheritance of this condition. Explain your reasoning. Name Relation age ВРМ Claire Grandparent; James' spouse 85yrs 99 bpm 45 bpm 41bpm 68bpm 40bpm 85bpm 86bpm 90bpm Grandparent; Claire’s spouse son to Claire and James; Indra’s spouse son to Claire and James; Mary’s spouse 87yrs 55уrs 53 yrs 49уrs 55уrs 54yrs 49уrs James Ricky Jimmy daughter to…

Construct a pedifree chart of the trait traced in the situation below The pedigree chart must be constructed with their names and genotypes at the bottom of every individual in the chart.

Tay-Sachs disease is a rare human disease in which toxic substances accumulate in nerve cells. The recessive allele responsible for the disease is inherited in a simple Mendelian manner. For unknown reasons, the allele is more common in populations of Ashkenazi Jews of eastern Europe. A woman is planning to marry her first cousin, but the couple discovers that their shared grandfather’s sister died in infancy of Tay-Sachs disease.a. Draw the relevant parts of the pedigree, and show all the genotypes as completely as possible. b. What is the probability that the cousins’ first child will have Tay-Sachs disease, assuming that all people who marry into the family are homozygous normal?

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