Larger subclonal clusters have been previously reported in the aging testis for mutations associated with Apert syndrome (Qin et al. 2007; Choi et al. 2008, 2012; Maher et al. 2016), Noonan syndrome (Yoon et al. 2013; Maher et al. 2018; Eboreime et al. 2022), Multiple Endocrine Neoplasia Type 2B (MEN2B) (Choi et al. 2012), Thanatophoric Dysplasias (Maher et al. 2016), ACH (Shinde et al. 2013), Pfeiffer syndrome (Maher et al. 2016, 2018), Hypochondroplasia, Crouzon, MEN2A, and Beare–Stevenson syndromes (Maher et al. 2018). The gene discussed is RET; the disease is hypochondroplasia.