A new immigration bill under consideration by the House Judiciary Committee would impose unprecedented restrictions on U.S. citizens seeking to sponsor the immigration of their family members, requiring that all parties submit to mandatory DNA testing as part of their visa applications.

H.R. 5203, the Visa Integrity and Security Act of 2016, would require that “a genetic test is conducted to confirm such biological relationship,” adding that “any such genetic test shall be conducted at the expense of the petitioner or applicant.”

A public letter from the American Civil Liberties Union protesting the bill notes that its provisions would require “even a nursing mother [to] undergo DNA testing to prove the biological relationship with her infant,” and “would amount to population surveillance that subverts our notions of a free and autonomous citizenry.” It is unclear how the bill would account for adopted children, or those who for a variety of other reasons might not fully share the DNA characteristics of their parents.

The requirement would likely be particularly expensive and onerous in countries where DNA testing facilities are not easily accessible.

“This bill would dramatically overhaul the U.S. immigration system, requiring U.S. citizens and their family members to undergo mandatory DNA testing even when there is no evidence of fraud,” said Joanne Lin, legislative counsel with the American Civil Liberties Union. “The rules would apply across the world, to people from all continents seeking to immigrate to the U.S. based on family relationships. Families have historically been a major engine of immigration to the United States, but the provisions this bill puts in place would have unprecedented consequences for that.”

In addition to the genetic testing requirements, which would be applicable across the globe, the bill also prohibits nationals and dual nationals of seven specified countries — Iran, Iraq, Libya, Somalia, Sudan, Syria, and Yemen — from obtaining any type of U.S. visa without undergoing enhanced security screening procedures.

Critics say these changes are discriminatory, targeting individuals based on their country of birth or ancestry rather than their own personal histories. Changes to visa rules contained in the bill would have major impacts on, for instance, students seeking to study at American universities, who would have to submit to onerous burden-of-proof requirements regarding their projected length of stay in the United States.

“The fact that Iran is on the list of specified countries and Saudi Arabia isn’t, despite its proponents citing 9/11 as a reason for its implementation, speaks volumes about the political motivations here,” said Jamal Abdi, executive director of the National Iranian-American Council, who also notes that there is no way for countries to be removed from the list without further legislation being passed. “The arguments underlying the proposed legislation show how foolish and backwards it is to designate people based on their nationality rather than their own personal behavior.”

Last year, H.R. 158 became law. The bill, targeting dual citizens of several Muslim-majority countries, prohibited their participation in the U.S. Visa Waiver Program. H.R. 5203 would further compound the difficulty of such individuals entering the United States, requiring them to obtain a Security Advisory Opinion (SAO) from the State Department before being approved for a visa. Obtaining an SAO could dramatically increase the amount of time it takes to obtain a U.S. visa, adding months or even years to the process.

The cumulative changes would “grind the process to a halt” for many seeking to immigrate to the United States, said Abdi, while making it nearly impossible for many others to visit the country for business, study, or professional purposes. “This bill is from the same family tree as previous anti-immigration legislation passed last year, with assistance from the extreme rhetoric of Donald Trump and others on the campaign trail,” Abdi said.

The new bill is sponsored by Randy Forbes, a Republican congressman from Virginia. At a press conference announcing the introduction of the bill earlier this month, Forbes cited the 2015 mass shooting in San Bernardino as providing an impetus. One of the shooters was a Pakistani citizen on a spousal visa. Pakistan is not one of the countries that would be affected by the law.

The bill was marked up by the Judiciary Committee on Wednesday, and is expected to proceed to a vote in the coming weeks.