BOSTON -- A new test tries to give men a heads-up on whether they could soon be bald.

Hair DX is sold by a California company that said the test searches genes for a variant that 95 percent of all bald men share.

Men who have it are at 60 percent risk of going bald before they're 40.

The DNA test is designed for men between the ages of 18 and 40.

All it takes is a simple mouth swab. Customers mail off their swab and get test results in three weeks.

The test is currently on sale online for about $149, but will soon be available through doctors' offices.

A Columbia University geneticist quoted in USA Today was skeptical of the test, saying it's hard to pinpoint the cause of baldness because few genes connected to hair loss have been identified.