The Rawhitis part in Caprine DNA study - 2009
A bit technical for some, this demonstrates the uniqueness of the Rawhiti goats, the population conserved by David Tuart, caught in the Pongakawa Bush, near Rotorua, New Zealand in 1998-1999.
Synopsis of “Genetic Characterization of the Goat Breeds: San Clemente Island, Myotonic, Galapagos, Rawhiti, Golden Guernsey, Damascus, and English and Their Genetic Relationship to other Spanish and Criollo Breeds."
Amparo Martínez Mátinez, Vincenzo Landi, Juan Vicente Delgado Bermejo
The original was in Spanish. Comments by D.P. Sponenberg throughout, and hopefully these are obvious as to source.
Excerpts, abbreviations, and diagram modified by D. Thomson
The analyzed samples included:
67 San Clemente (SC)
65 Myotonic (Texas and Tennessee bloodlines) (MYO)
30 Galapagos (GAG)
33 Rawhiti (RW)
16 Golden Guernsey (GG)
5 Damascus (D)
9 English (E)
Several USA Spanish goat samples were previously sent, and were included in the analysis.
These were studied in their own right, and also compared to Spanish breeds:
Blanca Andaluza (BA)
Blanca Celtibérica (BC)
Cabo Verde Island (CV)
DNA allelic frequencies were evaluated with 29 microsatellite loci examined.
As a general rule, individuals from Arapawa, Golden Guernsey, and most San Clemente goats were clearly distinct and clustered closely together within their breed. This means, basically, that these are likely to be populations with long-term isolation from others, and are therefore true breeds in the narrow genetic sense. Galapagos and Rawhiti also tended to isolate well from other breeds as unique clusters. In contrast, the Myotonic, US Spanish, Damascus, and English goats did not form distinct groups, and were located more closely to one another with the remaining breeds more isolated. This last may well reflect more “open” population structure to these last breeds, with more recent incursions of other goat breed types.
Additional analyses showed that US Spanish and Myotonic goats were very closely related to one another. Both are closely related to other Criollo, Spanish Island, or Peninsular breeds. This is consistent with their known history, although obviously more for the USA Spanish than for the Myotonic. San Clemente, Golden Guernsey, and Arapawa remain far from any of these, implying greater isolation by either founding population or isolation. This is important in assigning these priority for conservation – they clearly deserve separate programs, and are unlikely to fit well into a “composite Iberian-derived” population left over from the age of discovery taking goats around the planet.
Genetic distances between the breeds tended to be large, with the exception of Myotonic and Spanish goats. This is revealed in various branching diagrams showing relationships of the breeds, with the general trend being a diagram with a central point with each breed being a direct offshoot from the center.
The resulting breed diagram has breed clusters that are more defined than the original “few breed” analysis.
One cluster of breeds is clearly peninsular Iberian, including Murciana, Granadina, Blanca Andaluza, Blanca Celtibérica, Malagueña, and Serpentina. While these form a cluster, it is of interest to note that Alpine and Saanen form a “side cluster” of this group. What this means is somewhat uncertain, although likely relates to these as European breeds. Certainly the phenotype of Alpine/Saanen versus the others is quite distinct.
A second and somewhat looser group, is the “Spanish Island” breeds (Majorera, Palmera, Tinfereña) along with Cuban Criollo, Venezuelan Criollo, and Moxoto from Brazil. Interestingly, the Arapawa seems to fit best here, albeit with a very long branch from the group suggesting a distant relationship. This would be consistent with a foundation event from related goats, with subsequent long isolation. That interpretation is consistent with history. To the side of this main group are the Argentine Criollo and the Bolivian Criollo. (I don’t know which Argentine Criollos were included – Neuquino Criollos seem more crossbred phenotypically than do those from Formosa, which could be important). Again, this is consistent with inferred history.
A third very counter-intuitive and somewhat looser cluster is US Spanish, Myotonic, Anglo-Nubian, Damascus, and Boer goats. A subcluster in this loose group is San Clemente, English, Golden Guernsey, Galápagos, and Rawhiti. None of these cluster all that strongly, and so any implied relationship may not actually be all that close. Put another way, these likely each stand on their own pretty well.
Arapawa goats are distantly related to most others, with a tenuous but present relationship to Criollo breeds. They warrant isolated conservation. Rawhiti goats clustered distinctly from Arapawa goats, implying that they should be separately conserved rather than joined together. In addition, the few English goats likewise were distinct, so that any historic relationship is at this point swamped by the centuries of isolation of these populations. In one sense this is somewhat unfortunate as combining some of these three would have made conservation somewhat easier.
A summary for all would be that the submitted populations all passed the genetic test of being true genetic breeds. With few exceptions, in all cases the individuals clustered much better with each other than with any other group or breed. Hopefully this can help drive the conservation of the breeds.