Eventually, the bones in your baby's skull will build up enough minerals to completely fuse together, and those gaps will close. You may not have even noticed the smaller back fontanelle, which typically closes by the time a baby is around 3 months old, but is sometimes closed at birth.
The posterior fontanelle usually closes by age 1 or 2 months. It may already be closed at birth. The anterior fontanelle usually closes sometime between 9 months and 18 months. The sutures and fontanelles are needed for the infant's brain growth and development
<em>Substitution is a type of mutation where one base pair is replaced by a different base pair. The term also refers to the replacement of one amino acid in a protein with a different amino acid.</em>
