Three years have now passed, but the gene has not been identified.

In 2011, the gene responsible for the behavior was identified.

The gene responsible for the disease has not yet been identified.

The genes responsible for this association have not yet been identified.

To date, these genes have not been isolated or identified.

The gene responsible for this feature has not yet been identified.

By 1990 nearly all specific genes and enzymes had been identified.

"With a thousand genes identified, we are beginning to see what a cell is," he said.

For the other one-third of patients, the gene(s) involved has not yet been identified.

Four genes have been identified as members of the K gene family.