RNU5B-1 and Failure to thrive: Generalized hypotonia (OR = 37.3, P = 7.4 × 10−5), macrocephaly (OR = 30.6, P = 1.8 × 10−4), failure to thrive (OR = 24.7, P = 4.5 × 10−4), global developmental delay (OR = 22.1, P = 5.6 × 10−3) and abnormality of the eye (OR = 18.7, P = 1.4 × 10−3) were significantly enriched in individuals with RNU5B-1 variants (Fig. 2c).