Mutations in the sequence flanking the microsatellite at the KAP8 locus prevent the amplification of some alleles.

The microsatellite described for the glycine- and tyrosine-rich keratin locus (KAP8) in sheep was used to type nine large three-generation families comprising the AgResearch International Mapping Flock. The apparent non-Mendelian inheritance in these families suggested that some of the microsatellite alleles were not being amplified. Sequence analysis showed that a deletion within one of the published primer sites was the likely cause of the 'null' alleles. By redesigning the primer all alleles could be amplified.