What they found was 5 areas of the genome that had predictive potential for people being gay or straight. Combined, they were able to predict about 25% of what makes someone gay. The other 75% is environmental.
Note that some "environmental factors" may still be genetic in nature. For example there is strong evidence in animals that the prenatal environment has an impact on homosexual behavior. Which means that a mother's genetics can be correlated with her children's sexuality. Therefore a gene could impact homosexuality through changing the environment in the mother's womb. In that case the child having that gene would be correlated with the child being homosexual and the gene would show up in this study. But the differences between the child's genetics and the mother's would be an environmental factor.
I don't think it's making that strong a claim. They can't identify a specific gene. That's not quite "you are not born a homosexual." Plenty of studies over the years have shown statistically very significant genetic links. We just can't explain the exact mechanism yet.
What they found was 5 areas of the genome that had predictive potential for people being gay or straight. Combined, they were able to predict about 25% of what makes someone gay. The other 75% is environmental.
Note that some "environmental factors" may still be genetic in nature. For example there is strong evidence in animals that the prenatal environment has an impact on homosexual behavior. Which means that a mother's genetics can be correlated with her children's sexuality. Therefore a gene could impact homosexuality through changing the environment in the mother's womb. In that case the child having that gene would be correlated with the child being homosexual and the gene would show up in this study. But the differences between the child's genetics and the mother's would be an environmental factor.