37 Tex. Admin. Code § 28.43
A right thumbprint is required to be captured and included with each blood specimen collected. If the subject has no right thumb, then a left thumbprint shall be captured. The thumb must be rolled to capture the entire print. Signatures are required from the person collecting the sample and the subject providing the sample.
Source Note:The provisions of this §28.43 adopted to be effective June 27, 1996, 21 TexReg 5748.