WA’s first pre-pregnancy screening program will be offered to couples to find out if they are carriers for more than 450 disease-causing genes.

The pilot program will screen up to 250 couples in the Busselton region who are planning to have a baby.

Experts hope it will be the first step in a national program offered to all would-be parents.

The study is possible because of advances in genetic analysis including technology that can sequence genetic material for hundreds of disorders at a time.

The screening uses a simple saliva swab or blood test and couples can get the results within weeks.

It will check for recessive diseases, where the mother and father are unaffected but if both are carriers can face a one-in-four chance of having a child with the disorder.

Almost 90 per cent of couples at risk of having babies with devastating genetic conditions such as cystic fibrosis have no family history and no idea they are potential carriers.

The program is being run by the Harry Perkins Institute of Medical Research, the WA Health Department’s Genetic Services WA, PathWest and the Busselton Population Medical Research Institute.

Professor Nigel Laing, who heads the Harry Perkins’ Neurogenetic Disease Laboratory, said rare diseases and malformations caused half of all deaths in the first year of life.

The likelihood of a baby being born with one of three most commonly screened conditions —cystic fibrosis, fragile X syndrome or spinal muscular atrophy, which can cause paralysis — was comparable to the chance of having a child with Down syndrome.

“One in 50 people are carriers for SMA and if they partner with another carrier, they have a one in four chance with every pregnancy of having a baby with SMA,” Professor Laing said.

“The pilot program will test couples’ chances of passing on to their children severe genetic conditions including those that lead to death in the first years of life.”

Scientists had already identified the cause of more than 30 genetic conditions.

Federal Health Minister Greg Hunt announced in May that he wanted to offer carrier screening to all Australian couples.

Professor Laing said the results of the study were expected to pave the way for the Federal plan.

The project is supported by the Zac Pearson Legacy, which was set up by Olympic swimmer Todd Pearson and his wife Alisa to honour their 22-month-old son who died suddenly nine years ago.

Mrs Pearson said she did not want other parents to go through the unexpected loss of a child. “Hopefully, this will give information to parents about the possibility of a genetic disease before they conceive,” she said.