Question

A person with Swyer Syndrome has come in for genetic testing.

You have been tasked with examining their genetic code on their SRY Gene to understand what has caused them to develop dysgenesis symptoms.

Here is the code you found in the lab for one half of their Gene:



The other complimentary half of the gene has finally come back from the lab, from top to bottom as:

1.T

2.A

3.C

4.G

5.A

6.C

7.T

8.G

9.G

10.A

11.A

12.C





Pretend you are working with the patient and explain to them the cause of their condition based on only the evidence stated above. Please use a minimum of 3 sentences.

Answer 1

The 12 bases you gave on the complementary strand (5'→3': T A C G A C T G G A A C) pair to give a coding strand of 5'→3' A T G C T G A C C T T G, which encodes the amino acids Met–Leu–Thr–Leu and includes an intact ATG start codon. That means this sequenced segment of SRY looks functional, so the cause of the patient’s Swyer (46,XY gonadal dysgenesis) must be a damaging mutation elsewhere in the SRY gene (the other half you initially tested or a nearby regulatory region) that prevents SRY from acting as the testis-determining factor. Loss-of-function of SRY (from a missense, nonsense, frameshift, or regulatory mutation in the missing region) is the likely molecular explanation for their dysgenesis.