The DNA Certificate of Analysis itself is useful for identification purposes only.  However, having a DNA sample stored in laboratory conditions enables other tests to be performed on the sample in the future.  For any medically related testing of the DNA sample, please visit GeneTests under Other Links.  Disease testing is not related to DNA Connections.  DNA Connections performs storage and relationship testing only.

The DNA profile is listed on the certificate-the profile is made up of genes used for human identification.

Below is a draft cert that belongs to this sample profile -Yet it will serve as an example just the same.

The number designations on the same line as your name are alleles or more specifically the number of tandem repeats in that system. Each system is a position on the chromosome that we use for human identification. FGA, vWA, D3S1358 (and the rest)...are non-coding regions on each chromosome.

In each system, a person will have two alleles-one transmitted from their mother and one from their father. Below in FGA you have a 21 from one parent and a 23 from the other. In D7S820 you notice the zero (all subsequent certificates will be blank instead of displaying a zero), this indicates that you are a double 10 in that system; your father transmitted a 10 allele and so did your mother.

The naming convention for D21S11 is as follows:

D: DNA
21: Chromosome 21
S: single copy
11: 11th system described on Chromosome 21

FGA and vWA are just names for the actual gene.

A little more on the allele (repeat) designation. There are complex repeat patterns measured but the simplest ones would look like this: (AATG) (AATG) (AATG) 3 repeats (AATG) (AATG) (AATG) (AATG) (AATG) (AATG) 6 repeats The complex systems would include microvariants as seen in D21S11. This system is a complex tetranucleotide repeat, the repeating pattern looks like this: (TCTA)3 TA (TCTA)3 TCA (TCTA)2 (TCCA) The x.2 microvariant is primarily due to a 2base pair (TA) insertion. Anyway, the systems used are Short Tandem Repeats (STR's). The STR's are isolated using an enzyme that cuts the strand at the repeat location. How is the profile calculated? Each system has a certain number of repeats. From a statistical standpoint, we look at the frequency these repeats occur in each system. Therefore, in D21S11, if 32.2 is seen at a frequency of .0012 and a 29.3 is seen at a rate of .1236 the system frequency is calculated as follows: 2 (.0124)(.1236) = .00306, so when we look at several systems each system is multiplied using the product rule...so the frequency is extremely small. Let us say the eight other systems where hypothetically the same frequency then the number would be 2.3 x 10-23 or this can be expressed as a likelihood ratio by 1 / 2.3 x 10-23 or One in 41,857,050,000,000,000,000,000.