Parents of a 3-month-old infant bring him to the emergency room (er) after he has had a seizure. he has muscle rigidity, and the parents report they are of jewish ancestry. for what genetic disease should this infant be screened?

Tay-Sachs disease.

Explanation:

Tay-Sachs disease may be defied as a type of genetic disease that result in the destruction brain and spinal cord nerve cells. This disease occur due to the mutation in the  HEXA gene of the chromosome number 15.

The infantile Tay sach's disease is most common that are noticed in the infants of 3 months. The baby is not able to crawl or sit properly. Later on he loses his ability to move, suffer from seizures, hearing loss  and ultimately the death of the child.

Thus, the answer is Tay-Sachs disese.