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Sickle cell anemia is a genetic disorder...

Sickle cell anemia is a genetic disorder where the body produces an abnormal hemoglobin called hemoglobin S. Red blood cells are normally flexible and round, but when the hemoglobin is defective, blood cells take on a “sickle” or crescent shape. Sickle cell anemia is caused by mutations in a gene called HBB. It is an inherited blood disorder that occurs if both the maternal and paternal copies of the HBB gene are defective. In other words, if an individual receives just one copy of the defective HBB gene, either from mother or father, then the individual has no sickle cell anemia but has what is called “sickle cell trait”. People with sickle cell trait usually do not have any symptoms or problems but they can pass the mutated gene onto their children. There are three inheritance scenarios that can lead to a child having sickle cell anemia:
- Both parents have sickle cell trait
- One parent has sickle cell anemia and the other has sickle cell trait
- Both parents have sickle cell anemia
If both parents have sickle cell trait, then there is _______________of the child having sickle cell trait.

A

25 % risk

B

50 % risk

C

75% risk

D

No risk

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The correct Answer is:
To solve the question regarding the inheritance of sickle cell trait when both parents have sickle cell trait, we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Genotypes**: - The genotype for sickle cell trait is represented as "AS", where "A" is the normal hemoglobin allele and "S" is the sickle hemoglobin allele. - The genotype for sickle cell anemia is "SS", and the genotype for normal hemoglobin is "AA". 2. **Set Up a Punnett Square**: - Since both parents are carriers (AS), we can set up a Punnett square to determine the possible genotypes of their children. - The Punnett square will have the alleles from one parent on the top and the alleles from the other parent on the side. ``` A S ------------ A | AA | AS | ------------ S | AS | SS | ``` 3. **Fill in the Punnett Square**: - The combinations from the Punnett square will be: - AA (normal) - AS (sickle cell trait) - AS (sickle cell trait) - SS (sickle cell anemia) 4. **Determine the Ratios**: - From the Punnett square, we can see the possible genotypes: - 1 AA (normal) - 2 AS (sickle cell trait) - 1 SS (sickle cell anemia) - This gives us a ratio of: - 1 AA : 2 AS : 1 SS 5. **Calculate the Probability of Sickle Cell Trait**: - To find the probability of the child having sickle cell trait (AS), we take the number of AS outcomes (2) and divide it by the total number of outcomes (4). - Probability = Number of AS outcomes / Total outcomes = 2 / 4 = 1/2 or 50%. ### Final Answer: If both parents have sickle cell trait, then there is a **50% chance** of the child having sickle cell trait.

To solve the question regarding the inheritance of sickle cell trait when both parents have sickle cell trait, we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Genotypes**: - The genotype for sickle cell trait is represented as "AS", where "A" is the normal hemoglobin allele and "S" is the sickle hemoglobin allele. - The genotype for sickle cell anemia is "SS", and the genotype for normal hemoglobin is "AA". ...
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Sickle cell anemia is a genetic disorder where the body produces an abnormal hemoglobin called hemoglobin S. Red blood cells are normally flexible and round, but when the hemoglobin is defective, blood cells take on a “sickle” or crescent shape. Sickle cell anemia is caused by mutations in a gene called HBB. It is an inherited blood disorder that occurs if both the maternal and paternal copies of the HBB gene are defective. In other words, if an individual receives just one copy of the defective HBB gene, either from mother or father, then the individual has no sickle cell anemia but has what is called “sickle cell trait”. People with sickle cell trait usually do not have any symptoms or problems but they can pass the mutated gene onto their children. There are three inheritance scenarios that can lead to a child having sickle cell anemia: - Both parents have sickle cell trait - One parent has sickle cell anemia and the other has sickle cell trait - Both parents have sickle cell anemia Sickle cell anemia is a/ an ______________________ disease.

Sickle cell anemia is a genetic disorder where the body produces an abnormal hemoglobin called hemoglobin S. Red blood cells are normally flexible and round, but when the hemoglobin is defective, blood cells take on a “sickle” or crescent shape. Sickle cell anemia is caused by mutations in a gene called HBB. It is an inherited blood disorder that occurs if both the maternal and paternal copies of the HBB gene are defective. In other words, if an individual receives just one copy of the defective HBB gene, either from mother or father, then the individual has no sickle cell anemia but has what is called “sickle cell trait”. People with sickle cell trait usually do not have any symptoms or problems but they can pass the mutated gene onto their children. There are three inheritance scenarios that can lead to a child having sickle cell anemia: - Both parents have sickle cell trait - One parent has sickle cell anemia and the other has sickle cell trait - Both parents have sickle cell anemia If one parent has sickle cell anemia and the other has sickle cell trait, there is __________that their children will have sickle cell anemia and ___________will have sickle cell trait.

Sickle cell anaemia is

Sickle cell anaemia is

Sickle cell aneemia is

Sickle cell anemia is a genetic disorder where the body produces an abnormal hemoglobin called hemoglobin S. Red blood cells are normally flexible and round, but when the hemoglobin is defective, blood cells take on a “sickle” or crescent shape. Sickle cell anemia is caused by mutations in a gene called HBB. It is an inherited blood disorder that occurs if both the maternal and paternal copies of the HBB gene are defective. In other words, if an individual receives just one copy of the defective HBB gene, either from mother or father, then the individual has no sickle cell anemia but has what is called “sickle cell trait”. People with sickle cell trait usually do not have any symptoms or problems but they can pass the mutated gene onto their children. There are three inheritance scenarios that can lead to a child having sickle cell anemia: - Both parents have sickle cell trait - One parent has sickle cell anemia and the other has sickle cell trait - Both parents have sickle cell anemia The following statements are drawn as conclusions from the above data (Kenya). I. Patients with SCD (Sickle Cell Disease) are less likely to be infected with malaria. II. Patients with SCD (Sickle Cell Disease) are more likely to be infected with malaria. III. Over the years the percentage of people infected with malaria has been decreasing. IV. Year 2000 saw the largest percentage difference between malaria patients with and without SCD. Choose from below the correct alternative.

Sickle-cell anaemia is

Sickle -cell anaemia is:

Sickle-cell anaemia is :