Min (c. 1499-2006) (the name of the animal was given in honor of the oldest Chinese dynasty, which ruled exactly at the time when the baby clam was born), given to a specimen of the mollusk species Arctica islandica of the Venerid family, washed ashore in Iceland in 2006, whose age was determined by counting the growth rings on its shell. Min was recognized as the oldest individual (non-colony) animal ever discovered whose age can be accurately determined. Initially, the age of the mollusk was declared equal to 405 years, later it was increased to 507 years.
How can I ensure a similar (at least 300 years) life expectancy for my genetically modified superhumans, who are representatives of a new species of people?
Note: it is worth mentioning that at the time of the actions of my story, this new kind of improved people was at the level of development of the Stone Age, that is, if the average life expectancy in the Stone Age for ordinary people was about 30 years, then for them it should be 300-350 years without any medical intervention from the outside.
Also, considering some questions about their metabolic rate or the duration of the growing up process, I would like to mention that their metabolic rate practically does not differ from ours, just like growing up.