By detecting the expression levels of KRAS, JUN, RAP1B, and TNF genes, doctors can recognize the occurrence of IDD earlier and assess the degree of disease progression, as shown in the nomogram graph, where high expression of KRAS and TNF, and low expression of JUN and RAP1B, are associated with having IDD. The gene discussed is RAP1B; the disease is intervertebral disk degenerative disorder.