DNA Testing in Illinois: Legal Collection & At-Home Kits

You can test at GameDay DNA collection sites or use an at‑home cheek‑swab kit for private peace of mind. Illinois Child Support Services explains in its brochure What Parents Need To Know About Establishing Paternity that a DNA sample is obtained by swabbing the inside of a person’s cheek and that Child Support Services will help complete forms and schedule testing when paternity is in question, while the Illinois Department of Public Health’s page on paternity and birth records notes that legal paternity can be established by Voluntary Acknowledgment, administrative order, or court order—not by simply presenting DNA results alone.

Illinois uses the Illinois Parentage Act of 2015, which authorizes courts and administrative agencies to order genetic testing when parentage is at issue. Under the Parentage Act’s provisions on requirements and admissibility of genetic testing, the court or an administrative agency may order testing of the child and every person whose parentage is being adjudicated, tests must be conducted by an expert qualified as an examiner, and results meeting statutory thresholds can identify or exclude an alleged genetic parent, while legal summaries on paternity and DNA testing in Illinois explain that a man whose test shows at least a 99.9% probability of paternity is generally presumed to be the biological father and can be adjudicated as such unless rebutted.

Most legal paternity tests in Illinois use buccal‑swab (cheek‑swab) DNA samples from the child and the alleged father, and often from the mother. Illinois Legal Aid’s explainer What is a paternity test? notes that a paternity test compares the DNA of the child, mother, and alleged father—usually using cheek‑swab samples—to determine whether the man is the biological father, and Illinois family‑law guides such as Establishing Paternity in Illinois and How is DNA testing used in Illinois paternity cases? confirm that cheek‑swab DNA is the standard, court‑approved collection method, even though blood or other tissues are also allowed by statute.

For at‑home kits, use the sterile swabs in your kit, rub firmly along the inside of each cheek for the full time listed in the instructions, let the swabs air‑dry, and seal them in labeled envelopes before mailing. Illinois Child Support’s paternity brochure HFS 3282 states that Child Support Services uses cheek‑swab DNA collection when it schedules testing and that samples are obtained by swabbing inside the cheek, while legal guides like Paternity and DNA Testing in Illinois emphasize that only tests conducted by accredited labs in compliance with the Parentage Act’s chain‑of‑custody and expert‑qualification rules are admissible as legal evidence, even though home kits use the same basic swab technique.

GameDay DNA provides results by secure online portal or encrypted email, with printed reports available for legal tests. When testing is arranged through Child Support Services or the court, Illinois practice guides such as How is DNA testing used in Illinois paternity cases? explain that the court chooses the testing provider, the lab sends certified results to Child Support or the court, and then the Division of Child Support Services or the judge issues an Administrative Paternity Order, Administrative Order of Non‑Paternity, or judicial Paternity Order based on those results, with parents informed through official notices and orders rather than directly by the lab.

Yes—Illinois statutes set detailed rules for when genetic‑test results are admissible and what effect they have. Under the Parentage Act’s sections on admissibility and consequences of genetic testing, a written report of genetic testing from a qualified expert is admissible without live testimony if served within required time frames, and if an alleged parent declines to submit to court‑ordered testing, the court or administrative agency may adjudicate parentage contrary to that person’s position; Illinois family‑law analyses, including How is DNA testing used in Illinois paternity cases?, add that when testing shows a paternity index high enough to give a 99.9% probability, Illinois courts presume the man is the biological father and will typically enter a paternity order unless that presumption is successfully rebutted.

Either parent, the child (through a representative), or the state (through Child Support Services) may be involved in establishing parentage in Illinois. Illinois Legal Aid’s paternity test basics and the Parentage Act outline that a person who gave birth, a man who believes he is or is not the parent, a child through a guardian, or a government agency providing support may bring an action to adjudicate parentage, and practice guides such as Establishing Paternity in Illinois explain that when parents do not sign a Voluntary Acknowledgment of Paternity at the hospital, either parent can open a Child Support Services case or file in circuit court and request DNA testing under the Act.

In special situations—such as when an alleged genetic parent is deceased, refuses testing, or there are competing parentage claims—Illinois courts can still rely on genetic evidence under the Parentage Act. The Act’s provisions summarized in 750 ILCS 46 and discussed in legal articles like the DCBA Brief on genetic testing and Section 610 explain that courts may order genetic testing of the child and all individuals whose parentage is being adjudicated, consider independent testing results and expert testimony, and apply best‑interest rules when a child already has a presumed, acknowledged, or adjudicated parent, while Social Security and practitioner guides note that high‑probability test results, even using relatives’ DNA, can be combined with other evidence to establish paternity for inheritance and benefit purposes when direct testing of the alleged parent is impossible.