ATR and immunodeficiency disease: A phenomenon similar to chromothripsis has been observed in the autosomal recessive Seckel syndrome 1 (SCKL1, OMIM #210600), caused by homozygous and compound heterozygous mutation in ATR. SCKL1 is characterized by severe intrauterine growth deficiency, dwarfism, microcephaly, lymphoma (in few cases), but not immunodeficiency or ataxia [45].