Cuddling babies, or not, affects infants' gene expression, B.C. study finds

Infants that are held less by caregivers show lasting changes to genes involved in immune response and metabolism, according to a study of children from British Columbia.
Fussy babies who were held the least were underdeveloped for their age in five areas of the genome when they were tested more than four years later. Fussy babies in the high cuddling range were normal.
The study also found a “vast” range in the time caregivers spent in contact with the babies, from 200 minutes a day