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M Amills

Publications and source records attributed to M Amills.

21 records · Page 2Linked to original sources
PubMed1996

Primer-directed synthesis of a molecular weight marker.

Marker primer-directed synthesis (MPDS) is a technique that allows the easy synthesis of DNA base pair (bp) ladders. This method involves the amplification of a DNA target with two different sets of primers: a set of range primers, which will define the absolute length of the ladder, and a set of spacer primers which will determine the size difference between each one of the fragments of the DNA ladder. The ladders obtained with this technique can be used as molecular weight standards to analyse the size of DNA fragments. In this way, we have synthesized a 6 bp ladder ranging from 90 to 204 bp which results particularly useful in the typing of microsatellites in ethidium bromide (EB) or silver nitrate (SN) stained polyacrylamide gels.

Animals↗
PubMed1995

Nested PCR allows the characterization of TaqI and PstI RFLPs in the second exon of the caprine MHC class II DRB gene.

A nested polymerase chain reaction (PCR) method has been developed to obtain a specific amplification of the second exon of the caprine MHC class II DRB gene. The specificity of this method has been verified by cloning and sequencing the PCR product and comparing its sequence to 21 previously published caprine DRB second exon allelic variants. Nucleotide identity between this sequence (Caae-DRB23) and other caprine DRB alleles ranged between 85.6% (Caae-DRB22) and 96.5% (Caae-DRB5). Caae-DRB5 and Caae-DRB23 sequences diverged in five amino acid substitutions (70, 71, 73, 74, 78), all of them placed at the antigen binding site. Likewise, the restriction polymorphism of the caprine DRB second exon has been analyzed and two different restriction patterns have been found depending on the presence or absence of a TaqI site and a PstI site at positions 122 bp and 241 bp of the PCR product respectively. TaqI and PstI RFLPs were also analyzed in other artiodactyla species. While PstI RFLP was found not only in goats but also in cattle, sheep and pigs, TaqI RFLP was only detected in goats. In all of these species close associations were detected between the presence of TaqI and PstI restriction sites and amino acid substitutions at positions 40 and 78 respectively, suggesting that PCR restriction fragment length polymorphism (RFLP) could be a useful tool in relating amino acid substitutions at critical positions with disease resistance.

Amino Acid Sequence↗