Sickle Cell Disease Case Study. What would be the sequences for the normal and m

Question

Sickle Cell Disease Case Study. What would be the sequences for the normal and mutant alleles?

I am having trouble understanding how the sequencing works. Please answer all questions. Any helpful explanations for future reference would be greatly appreciated.

Sickle Cell Disease Case Studiy Part 1. Sickle Cell Disease (Sickle Cell Anemial The main oxygen-carrying protein in red blood cells is The hemoglobin tetramer has two___-globin and two__-globin proteins. Individuals with a mutant allele for the -globin gene sequence can have sickle-shaped red blood cells. Those with one mutant allele for the -globin gene sequence have sickle cell- while those with two mutant alleles for the same gene sequence have sickle cell__. r the same gene sequence have sickle cell . Part 2.Gene to Protein: Modeling transcription and translation Hemoglobin Sequences Below are the coding strands of the normal and mutant (sickle cell) -globin sequences. The difference in the sequences is in bold. Normal allele 5' ATG GTG CAC CTG ACT CCT GAG GAG AAG... 3' Mutant allele 5' ATG GTG CAC CTG ACT CCT GTG GAG AAG... 3'

Explanation / Answer

Part-I:

1) The main oxygen-carrying protein in red blood cells is Hemoglobin.

2) The hemoglobin tetramer has two alpha () globin’s and two () globin’s.

3) Individuals with a mutant allele for the -globin gene sequence can have sickle-shaped red blood cells.

Those with one mutant allele for -globin gene sequence have sickle cell HBA HBs condition.

Those with two mutant alleles for the same gene sequence have sickle cell HBs HBs condition.

Part-2:

Based on the given data,

I:

Coding:    5’-ATG-GTG-CAC-CTC-ACT-CCT-GAG-GAG-AAG-3’

Template: 3’-TAC-CAC-GTG-GAG-TGA-GGA-CTC-CTC-TTC-5’      

mRNA:    5’-AUG-GUG-CAC-CUC-ACU-CCU-GAG-GAG-AAG-3’

tRNA:      3’-UAC-CAC-GUG-GAG-UGA-GGA-CUC-CUC-UUC-5’

protein:       +3HN-Met-Val-His-Leu-Thr-Pro-Glu-Glu-Lys-COO-

II:

Coding:    5’-ATG-GTG-CAC-CTC-ACT-CCT-GTG-GAG-AAG-3’

Template: 3’-TAC-CAC-GTG-GAG-TGA-GGA-CAC-CTC-TTC-5’      

mRNA:    5’-AUG-GUG-CAC-CUC-ACU-CCU-GUG-GAG-AAG-3’

tRNA:     3’-UAC-CAC-GUG-GAG-UGA-GGA-CTC-CUC-UUC-5’

protein:       +3HN-Met-Val-His-Leu-Thr-Pro-Val-Glu-Lys-COO-

The type of mutation is: Point Mutation

Sickle cell anemia is a blood disorder witnessed by improper folding of hemoglobin when hemoglobin levels are low and affects the oxygen carrying capacity of an individual. It is caused by alteration (mutation) in the protein hemoglobin. The point alteration is caused in -globin chain of hemoglobin.

Based on the molecular analysis of in gene that codes for -globin chain of hemoglobin, the GAG at 6th position codes for glutamic acid and the middle base “A” (adenine) is replaced with T (Thymine), which results change in the sequence GAG to GTG. Hence, the GTG codes for Valine. This mutation is called point mutation.

The glutamic acid is a hydrophilic amino acid it is replaced by a hydrophobic amino acid called valine. Thus, change in the amino acids results change in the hydro properties in the -globin chain of hemoglobin, and it leads to aggregation of the RBC, and form tetramers. These tetramers cannot bind to oxygen, thus due to deprivation oxygen makes the RBC to attain sickle cell shape.

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.