IGFBP2 and neurodevelopmental disorder: In the present study, a copy number loss 15q11.2 (22754322–23109890)×1 (GRCh37) (Supplementary Table S1) containing the 15q11.2 recurrent region (BP1-BP2) associated with the occurrence of neurodevelopmental disorders has been classified by various laboratories as a variant of VUS, LP, or P (6/1/2 laboratories, respectively), demonstrating that laboratories encountered confusion regarding the categorization of CNVs with reduced penetrance which are not rare in the population.