A METHOD FOR THE PURIFICATION AND RECOVERY OF GENOMIC DNA FROM AN HLA-DQA1 AMPLIFICATION PRODUCT AND ITS SUBSEQUENT AMPLIFICATION AND TYPING WITH THE AMPLITYPE(R) PM-PCR AMPLIFICATION AND TYPING KIT

DNA from plucked single hairs from ten individuals was extracted by tw o different methods and subsequently amplified and typed using the Amp liType(TM) HLA DQ alpha Forensic DNA Amplification and Typing Kit. The remaining untyped portions of the DQA1 amplification products were st ored refrigerated or frozen for two weeks and subsequently purified us ing Centricon(TM) 100 microconcentrators. Genomic DNA was recovered fr om the DQA1 amplification PCR and used again as a template for a subse quent multiplex PCR. Twenty mu L of each retentate were amplified and typed with the AmpliType(R) PM PCR Amplification and Typing Kit. All t yping results were consistent with DQA1 and PM results of control hair s and reference blood samples from the donors and all results were con sistent with those obtained when the samples were typed solely for PM. The DQA1-Centricon(TM) 100-PM approach is useful when the genomic DNA from an evidentiary sample has been used completely for HLA-DQA1 typi ng, so that only the amplified product is remaining. The typing of fiv e more genetic markers can be achieved from a HLA-DQA1 sample, so addi tional information for identification purposes could be provided. Howe ver, genomic DNA as well as the DQA1 product are recovered and the lat ter will also serve as a template in the subsequent PM amplifications. Therefore there will be more DQA1 product after the PM amplification than would be expected when only genomic DNA was used as a template. T hus certain practices should be considered when reading the types from PM probe ships if this DQA1-CentriconTM 100-PM approach is used.