Okla. Stat. tit. 10, § 10-7700-508: Specimen from potential father unavailable –

Additional sources of specimens for testing.

A. Subject to subsection B of this section, if a genetic-

testing specimen is not available from a man who may be the father

of a child, for good cause and under circumstances the court

considers to be just, the court may order the following individuals

to submit specimens for genetic testing:

1. The parents of the man;

2. Brothers and sisters of the man;

3. Other children of the man and their mothers;

4. Other relatives of the man necessary to complete genetic

testing; and

5. Any other custodians of genetic material.

B. Issuance of an order under this section requires a finding

that a need for genetic testing outweighs the legitimate interests

of the individual sought to be tested.