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STR Analysis is an important term in the field of DNA testing and genetic sequencing. STR stands for Short Tandem Repeats and STR testing is a type of analysis that compares specific loci on DNA samples that are used in relationship testing.

Include additional participants where possible

Since the STR testing is based on the comparison on common DNA, it is recommended to submit the sample of any known parent of the individuals being tested. This will assist in separating the maternal and paternal DNA of the individuals being tested and therefore facilitate the identification and evaluation of the common DNA.

Visit Interpreting the result of a DNA Relationship test for more information on how to understand the result of your STR analysis.

About Short Tandem Repeat analysis

Essentially, STRs are short repeated DNA sequences. DNA consists of repeated sequences of genetic material known as nucleotides. The repeated sequences consist of what are known as base pairs. DNA can have 4 different base pairs, these being: adenine, guanine, cytosine, and thymine.  An STR sequence might thus be a repetition of the ATAT (adenine-thymine) base pair. From one person to the next, the number of repeats may vary though this would only happen on some STR loci; a phenomenon which is not quite understood by scientists. These differences in STRs can help to locate differences between people.