The amelogenin gene is known as the sex determining gene simply because it determines the gender of a person. This gene is present on both the X chromosome and the Y chromosome. Most DNA testing companies will test for this gene with most DNA tests and though clients may think this futile it is a control measure to ensure that the correct samples have been processed as the propensity to err means that clients carrying out the DNA test may sometimes place the wrong swabs in an envelope. In cases of deceased persons who cannot be identified as male or female, then testing this gene will make it possible to classify the remains. The gene is tested in other cases. What must be noted is that sometimes male DNA samples when tested can be detected as female DNA samples. This happens in extremely rare cases when the amelogenin gene happens not to be present on the Y chromosome in males. This deletion of the gene is extremely rare and advice regarding it will be given should the need arise.