Amelogenin
Amelogenin might sound impressive or technical but it’s actually something we all have inside us. It's a protein that exists in tooth enamel, which scientists believe is related to tooth growth and development.
The function of it isn’t fully understood by scientists yet, but most people believe that it’s able to organise ‘enamel rods’ while teeth develop in children, while also helping to maintain tooth enamel. It also seems to strengthen the root surfaces of teeth by encouraging increases of a calcified substance called cementum.
Amelogenin is important when it comes to DNA testing because it can be used to identify whether a human sample came from a male or female source. Male and female samples perform differently in test conditions, which means that it is possible to determine the gender of whomever a sample came from fairly easily using Amelogenin.
Some errors in the test results can occur, though, due to rare mutations which result in a misinterpretation of a sample as being female when it’s actually from a male person. The rate of error, however, is very low, and in a study which involved 1224 people the rate of successful gender attribution was at 99.84% with 1222 out of 1224 results correctly identified as male or female and only two of these incorrectly identified as female when they were actually male.
Some genetic testing on people who were of an Indian ethnic origin showed a higher incidence of the aforementioned rare mutations which cause bogus test results. Amelogenin is also one of the markers used in paternity tests and it has been the subject of thousands of studies.
