Biochem 68

Question 1

What are the findings in Lesch-Nyhan syndrome? (6)

Answer 1

1) Intellectual disability
2) Self-mutilation
3) Agression
4) Dystonia
5) Gout
6) Hyperuricemia

Question 2

What is the treatment for Lesch-Nyhan syndrome? (2)

Answer 2

1) Allopurinol (inhibits xanthine oxidase)

2) Febuxostat (2nd line)

Question 3

Which enzyme acts upon PRPP to form phosphoribosylamine in 1st committed step of de novo purine synthesis?

Answer 3

Phosphoribosyl Pyrophosphate Amidotransferase (UW 2067)

Question 4

What does the genetic code mean by it is unambiguous?

Answer 4

Each codon specifies only 1 amino acid

Question 5

What is meant by the genetic code is degenerate/ redundant?

Answer 5

More than one codon can code for a particular amino acid (UW 1424)

Question 6

Which amino acids are exceptions to the degenerate/redundant rule of the Genetic code? Which codons? (2)

Answer 6

1) Methionine (AUG)

2) Tryptophan (UGG)

Question 7

What is meant by the genetic code is commaless, nonoverlapping?

Answer 7

Read from a fixed starting point as a continuous sequence of bases (exception: some viruses)

Question 8

What is meant by the genetic code is universal? What is an exception?

Answer 8

The genetic code is conserved throughout evolution (Exception: mitochondria in humans)