Naked mole-rat mortality rates defy Gompertzian laws by not increasing with age

TLDR

The naked mole‑rat, the longest‑lived rodent with a maximum lifespan exceeding 30 years, shows delayed or attenuated age‑related physiological decline. The study aimed to determine whether this species follows Gompertzian mortality laws, i.e., an exponentially increasing risk of death with age. Researchers compiled and analyzed a large historical dataset of more than 3,000 naked mole‑rat lifespan records. Kaplan–Meier analysis of these records shows that a substantial fraction survive to 30 years and that their age‑specific mortality hazard remains flat, contradicting Gompertzian expectations and confirming the species as a non‑aging mammal and a unique biogerontological model.

Abstract

The longest-lived rodent, the naked mole-rat (Heterocephalus glaber), has a reported maximum lifespan of >30 years and exhibits delayed and/or attenuated age-associated physiological declines. We questioned whether these mouse-sized, eusocial rodents conform to Gompertzian mortality laws by experiencing an exponentially increasing risk of death as they get older. We compiled and analyzed a large compendium of historical naked mole-rat lifespan data with >3000 data points. Kaplan-Meier analyses revealed a substantial portion of the population to have survived at 30 years of age. Moreover, unlike all other mammals studied to date, and regardless of sex or breeding-status, the age-specific hazard of mortality did not increase with age, even at ages 25-fold past their time to reproductive maturity. This absence of hazard increase with age, in defiance of Gompertz’s law, uniquely identifies the naked mole-rat as a non-aging mammal, confirming its status as an exceptional model for biogerontology.