A new poll shows parents are split over whether their newborns should be screened for fragile X syndrome, the most common type of inherited mental disability.

The findings fuel an ongoing debate over which conditions should be part of mandatory newborn screening programs in the US.

Fragile X syndrome, or FXS, brings the debate into sharp focus, because there is currently no cure for the condition. What’s more, not all kids with the gene mutation that causes FXS will have disabilities, so parents may end up worrying unnecessarily.

On the other hand, affected families may find it easier to prepare for their kids’ special needs if they know about them early on. Currently, FXS isn’t diagnosed until the child is at least three years old.

The study

About one in 4,000 boys and one in 6,000 girls are born with the full mutation. The disease is less common in girls because the gene is located on the X chromosome.