For this project, we were tasked with choosing a case on a genetic disorder and providing information as a genetic counselor. We were to help the case family make a decision on whether they should have children and wrote a letter to the family. I chose to a help a family with a history of thalassemia. By creating a Punnett square and pedigree chart, I was able to explain the pattern of inheritance to the family. The letter applies to the communicate skill through our explaining and helping of the family. Below is my letter.
Letter to Clients
June 9th, 2020
Mr. and Mrs. Andino
Dear Mr. John Andino and Mrs. Sophia Andino:
I am writing to you as a Genetic Counselor reviewing your case. My name is Livia Kola and I am providing information on thalassemia as it pertains to your situation.
Thalassemia is an inherited blood disorder that affects hemoglobin production in the body, leading to fewer red blood cells. This disease can be categorized in minor, intermedia, or major forms depending on the severity. Mutations of the HBB or HBA1 and HBA2 gene cause beta or alpha thalassemia, respectively. The disease can cause fatigue, slow growth, and weakness along with abdominal swelling and bone deformities. Those with severe cases receive blood transfusions often and have a normal life expectancy, but complications may make the disease fatal before the age of thirty.
Upon reading your case, I have discovered that both of you are carriers for the thalassemia trait but display no symptoms. Being carriers for the disease means that both of you have a heterozygous genotype. Additionally, Sophia has a family history with the disease along with a brother that is affected by a major form of the disease. This is important in determining the likelihood that your children will be affected.
Constructing a Punnett Square to show inheritance allows us to see the probability that your children will be affected. Because thalassemia is autosomal recessive, your children would need a homozygous recessive genotype to be affected. Additionally, thalassemia is not sex-linked, meaning that it is just as likely to affect a male as it is a female. After studying the Punnett Square for your case, I can see that your children have a 25% chance to be affected, 50% chance to be carriers, and 25% chance to be completely unaffected.
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Having children in your situation is a risk and will likely result in many sacrifices that need to be made. However, people with thalassemia can live an incredibly full and happy life regardless of any health complications. It’s clear that you want a baby, and I would recommend trying for your first child. Remember, however, if your child is born with a major form of thalassemia, they will need large amounts of medical attention through blood transfusions, iron regulation, and sometimes removal of swollen abdominal organs.
Fortunately, some options test for diseases before birth. One is prenatal testing or chorionic villus sampling. In this test, sample cells are taken from the placenta and tested for genetic diseases. This can be done as early as ten weeks into the pregnancy. Depending on the results, you can choose to terminate the pregnancy. Another option is preimplantation genetic diagnosis done through in vitro fertilization. Eggs and sperm are combined outside the body to form an embryo which can then be tested for genetic disorders. The embryos that are free of genetic problems can be implanted into the uterus. Both these methods are expensive, however, and may not be suitable options for your family. If your child is born with a severe case of thalassemia, a stem-cell or bone marrow transplant may be an option, but it is difficult to find a suitable donor.
Know the risks and accept the sacrifices. Remember that your child can live a perfectly happy life, regardless of the disease.
Sincerely,
Livia Kola, MS
Certified Genetic Counselor
1212 Fake St, Rubber Duck, Ohio