"Number variants" refers to different versions or forms of a specific thing. It means that there are variations or different options available with numbers. Full definition
They found eight locations in the genome with copy number variants associated with schizophrenia risk. (sciencedaily.com)
With its large sample size, this study had the power to find copy number variants with large effects that occur in more than 0.1 percent of schizophrenia cases. (sciencedaily.com)
«While we're all walking around with copy number variants in our DNA, many of us don't have autism,» Cantor notes. (scientificamerican.com)