Most of human tooth agenesis cases are caused by genetic factors and mutations in AXIN2, EDA, LRP6, MSX1, PAX9, WNT10A, WNT10B, and BMP4 are known to cause tooth agenesis (Yu et al., 2016, 2019a,b; Wong et al., 2018). The gene discussed is MSX1; the disease is tooth agenesis.