Screen for all CF-causing CFTR variants in CFTR2 to reduce false-negative NBS in infants with rare variants, which is more common in infants who are American Indian, Asian, Black, Hispanic, or multiracial. This increases the percentage of infants who will have two CFTR variants detected, which shortens the time to diagnosis and initiation of treatment. This evidence concerns the gene CFTR and cystic fibrosis.