Question

1) What is a specific case in which genetic screening has saved and improved the quality of life for an individual through diet modification?

A) Duchenne's muscular dystrophy

B) cystic fibrosis

C) Prader-Willi syndrome

D) phenylketonuria

E) Down syndrome

2) Why are mitochondrial defects surprisingly prevalent?

A) Damage to DNA due to reactive oxygen species is much higher.

B) Mitochondrial DNA is not protected by histones.

C) Mitochondrial contain few repair systems.

D) Mitochondrial DNA has a much higher mutation rate than nuclear DNA.

E) all of the above

Answer 1

1) What is a specific case in which genetic screening has saved and improved the quality of life for an individual through diet modification?

A) Duchenne's muscular dystrophy- This disease is characterized by the loss of dystrophin. It cannot be corrected by diet formulation.

B) cystic fibrosis- It is caused by the mutation in the CFTR gene. In this, the person produces large amount of mucus. It cannot be corrected by diet formulation.

C) Prader-Willi syndrome- It is caused due to abnormality in many genes. It cannot be cured by diet formulations.

D) phenylketonuria- It is caused by the inability of an individual to metabolize amino acid phenylalanine. This can be cured by phenylalanine low diet or a PKU diet.

E) Down syndrome- It is caused by the trisomy of chromosome 21. It cannot be corrected by diet formulation.

So, the correct answer is D.

2.  

2) Why are mitochondrial defects surprisingly prevalent?

A) Damage to DNA due to reactive oxygen species is much higher.- This is correct as mitochondria have more ROS in it.

B) Mitochondrial DNA is not protected by histones.- Mitochondrial DNA is not bound with histones as it resembles prokaryotic DNA.

C) Mitochondrial contain few repair systems.- There is a very less repair system so damage is not repaired.

D) Mitochondrial DNA has a much higher mutation rate than nuclear DNA.- The rate of mutation is also very high in mitochondria.

E) all of the above- So, the correct answer is E.