Trillions of mutations in our cells may transform each of us every day

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Beyond Inheritance

Roxanne Khamsi, Riverhead Books (21 April)

There are around 30 trillion cells in your body and about 1 per cent of them get replaced every day. But this process is far from perfect. The DNA in new cells contains many mistakes, or mutations: there may be trillions of new mutations in your body every day.

“You are a slightly different genetic version of yourself today from yesterday, and will be different yet again tomorrow,” writes Roxanne Khamsi in her book, Beyond Inheritance: Our ever-mutating cells and a new understanding of health .

These mutations range from a change in a single DNA letter to the loss of an entire chromosome, such as the X or Y . A lot of mutations are lost when cells die, but many are passed on, building up over time.…