WASHINGTON (AP) — If America is a nation of immigrants, it's also a nation of immigrants' husbands, wives, parents and children — and their brothers, sisters, nieces and nephews, too.

That could begin to change under legislation being written in the Senate, where the nation's longstanding emphasis on family-based immigration is coming under scrutiny.

Unlike most other industrialized nations, the U.S. awards a much larger proportion of green cards to family members of U.S. citizens and permanent residents than to foreigners with job prospects here. About two-thirds of permanent legal immigration to the U.S. is family-based, compared with about 15 percent that is employment-based, according to the Migration Policy Institute. The remainder is largely humanitarian.