Each of the following quotations contains a grammatical error:
1. This process is one of several that is required to maintain nuclear SREBP1-c at very low levels… –Yeshiva University website
2. A study designed by Drs. Liu and Clarke is one of several that is slated to be included in the pilot run. –Georgetown University website
3. Steve Wozniak Is One Of The Few People Who Has Met The Kimye Baby –Business Insider
4. Henry [Kissinger] is one of the few who has the trust of the keepers of the secrets. –William Safire
The error is using a singular verb with a relative pronoun whose antecedent is plural.
1. The antecedent of that is not one, but several. “This process” is only one of several processes required to maintain the protein described: “several that are required.”
2. The antecedent of that is not one, but several. The pilot run will include several studies: “several that are slated.”
3. The antecedent of who is not one, but few: “one the few people who have met.”
4. The antecedent of who is not one, but few. “one of the few who have the trust of the keepers of the secrets.”
Agreement errors are often the result of “the law of attraction”: the tendency to make a verb agree with the nearest noun or pronoun that precedes it. Here is an error created by the law of attraction:
Incorrect: She is the only one of the board members who are in favor of more money for the arts.
Correct : She is the only one of the board members who is in favor of more money for the arts.
She is the antecedent of who. “She” is the only one in the group who holds that opinion.
More often than not, agreement errors with “one of x” go unnoticed in speech. A perusal of many reputable sites will show that they often go unnoticed in writing as well.
Professor Paul Brians (Common Errors in English Usage) acknowledges that the following sentence is incorrect according to formal grammar:
“Pistachio is one of the few flavors that appeals to me.”
But he feels that the only context in which one needs to worry about getting it right is when “taking a test on English grammar.” Otherwise, “sophisticated speakers” may trust to their native inner ear for what “sounds right.”
The Chicago Manual of Style is more decisive, declaring that “A relative pronoun takes its number from its antecedent.” Chicago offers these examples of correct usage:
[It is] one of the few countries that cultivate farm-raised fish as a staple.
She is one of those people who are famous just for being famous.
He is the one among them who is trustworthy.
Careful writers will pay attention to the difference.