Researchers have discovered a possible reason for why some young children are more susceptible to ear infections than others. The recent findings may require a revision of some textbooks. It has long been noted that certain children frequently battle with middle-ear infections such as glue ear. This is a buildup of fluid in the ear chamber. Updated understanding of how the ear develops and functions holds the key to understanding this childhood phenomenon.

While studying lab mice, it was found that the lining of the middle ear chamber can come from two different types of tissue: Endoderm and neural crest cells are the options. Endoderm tissue develops a protective and cleansing lining of cilia. These small hair strands aid in keeping the middle ear clean and are also what prove to be especially effective in fighting off infection. This offensive mechanism ensures a well-swept environment in which fluid has a difficult time building up.

On the other hand, neural crest cells are smooth and hairless. This allows fluid and debris to collect with less difficulty resulting in more infections. Scientists are unsure as to why there are two types of cells. Birds and reptiles, for example, do not have this option; it may be due to the number of bones in the middle ear. The three bones in a human ear require room for movement.

Just why the body is programmed to have one or the other tissue type is still uncertain. However, what is known is that certain textbooks will need to be revised. Previously, it was thought that the development of the endoderm tissue was merely a continuation of the lining in another part of the ear—this, at least, has been cleared up. It is hoped that further study can help improve the treatment of childhood ear infections and other middle ear disorders.