GPRC5B and obesity due to melanocortin 4 receptor deficiency: Firstly, the sample size was insufficient to detect associations of obesity with low frequency alleles (1p31.1/NEGR1, 10q11.22/GPRC5B, and 16p12.3/NPY4R), although it was sufficient to find associations with 11q11/OR4P4/OR4S2/OR4C6, and 1p21.1/AMY1 CNs.