Recently, a genomic mutational constraint map using variation over 76,000 human genomes reveal that loss-of-function mutations in LRP1 are highly significantly underrepresented (76), suggesting strong selection against haploinsufficiency for LRP1. A recent study by Yan et al. (77) identified mutations in LRP1 in developmental dysplasia of the hip patients and these missense mutations results in reduction of LRP1 protein levels thereby inducing loss of LRP1 function. The gene discussed is LRP1; the disease is developmental dysplasia of the hip.