LAMUT, IFUGAO— This scientific discovery will startle you to sit upright from a couch potato position.
But then, scientific discoveries and breakthroughs, sometimes dubbed as “amazing,” are not accidental or “wild guesses” but are labors of diligence and hard work.
A big bulk of the native pig subpopulation in two provinces in Cordillera Administrative Region (CAR) traces its roots to a similar and ancient ancestor lineage; a government study has concluded.
DNA (Deoxyribonucleic acid) testing, the molecule that carries genetic information for the development and functioning of an organism, has proven that native pigs long existent in Cordillera Administrative Region (CAR) have the same ancestral connections, if compared with other Philippine pigs in other regions.
The study conducted in the province of ifugao and Kalinga, in CAR.
Native pigs in the provinces of Ifugao and kalinga, chosen study sites by the Institute of Biological Sciences of the University of the Philippines, Los Banos, Laguna, “possess unique mtDNA haplotypes that are absent in other Asian and European pigs, ” the study revealed.
Haplotype is a group of genes within an organism inherited from a single parent.
Titled “Phylogenetic Study of Philippine Pigs (Sus srofa L,) from Ifugao and Kalinga Based on Mitochondrial DNA D-Loop Analysis,” the study was spearheaded by the Institute of Biological Sciences, Institute of Animal Science of UP, in close coordination with College of Agriculture and home Sciences, of Ifugao State University.
It was performed by research specialists Elpidio B. Basilio Jr., Rick Julius D. Cruz, Renato S. A. Vega, Ma. Genaleen Q. Diaz, Merlyn S. Mendioro, Genevieve May B. Aquino-Ang, Kuan Yi Li and Rita P. Laude.
Many rural families in CAR still adhere to raising purely native pigs for home consumption, for traditional and cultural uses. These, aside from raising other domesticated pigs for livelihood.
Native pigs are usually found in remote barangays in the different provinces in CAR and they form part of the cultural traditions of the highlanders in the Cordillera Mountains.
Sequence polymorphisms (presence of two or more variant forms of a specific DNA sequence) of D-Loop (control region) in mitochondrial DNA were employed by the research-specialist as these are commonly used to analyze intra-species evolution and divergence.
Conduct of the study was approved by the Institutional Animal Care and Use Committee of the College of Veterinary Medicine of UP, Los Banos,
Ear tissue samples were collected from 79 native pigs (41 tissue samples from native pigs in Kalinga and 38 from native pigs in Ifugao).
In Ifugao, samples were taken from the municipalities of Banaue (3), Lamut (7), Hungduan (7), Lagawe (13), Alfonso Lista (3) and Aguinaldo (8).
Ifugao samples collected came from remote areas in the municipalities, or deep inside the Cordillera hinterlands with limited road access.
Samples taken in Kalinga province were 17 in Tabuk City, 15 in Tanudan, and 6 in Lubuagan, explained the specialists.
Kalinga samples collected were near the cities of Tabuk and Tugeugarao with easily accessible roads for transport and trading of pigs.
Close relationship between the pig samples taken was also associated with the relative geographical distance between the two provinces, the researchers explained.
For example, the researchers noted the provinces belong to one region (which is CAR) and share similar practices like the use of native pigs for different rituals.
Due to the geographical proximity and cultural similarity, pig commerce is very highly hi probable, the researchers noted.
Purposive sampling was performed following Food and Agriculture (FAO) guidelines on performing molecular diversity rules, to ensure what the research-specialist explained of ensuring that “sampling procedure was not biased and animals were unrelated with each other.”
Interviews were conducted with those in possession of native pigs prior to pre-collection who assured researchers their native pigs were not related to other native pigs in their respective communities and that they procured their native pigs from other provinces in CAR.
Utilizing V-cut ear-notching, ear tissues approximately 1 cm. were incised from the outer ear. To prevent DNA contamination between samples, strict aseptic conditions were maintained. The incised tissues were carefully transferred to microcentrefuge tubes containing 100 per cent ethanol, stored in minus 20 degrees freezer then shipped immediately to UP, Los Banos.
These were promptly transferred to minus 80 degrees centigrade for long-term storage for use on genome DNA extraction procedure, the specialists specifically explained.
In the DNA study, there were five haplotypes that surfaced in the Ifugao and Kalinga pig subpopulations and identified under the cluster Type 1 Lanyu, a unique pig native to Taiwan.
The study came to the conclusion that while there is a presence of different haplotypes among Philippine pigs, such case is different in native pigs in Ifugao and Kalinga which underwent DNA scrutiny.
But the haplotypes discovered in the study for the Ifugao and Kalinga samples “characteristic nucleotide substitutions that are only present in the mtDNA D-Loop sequences from Type II Lanyu.”
Based on such finding, two hypothetical scenarios may explain the origins of Philippine pig subpopulation in Ifugao and Kalinga provinces.
“The presence of unique, duplicate DNA motif, or explained as “nucleic acid sequence pattern that possess some biological significance such as DNA binding sites for a regulatory protein, like transcription factor,” suggests that the Philippine pigs in the study either potentially share a common ancestor.
Researchers from Ifugao State University who joined the UP team offered a hypothesis that with the DNA finding a foregone conclusion, it would be prudent to assume that such a case of pig subpopulations in other provinces in CAR may follow suit.
Their hypothesis is not far-fetched. It can be recalled that rural dwellers in other provinces in CAR, whenever they replenish their pig sties after having disposed of pigs they raised, are very picky or very particular in choosing piglets they intend to raise.
It is a common characteristic or trait of rural dwellers to trace the origin of a piglet being offered for sale, whether it came from an old stock, whether the parents of the piglet was not tainted with non-native ( in other words pigs that are mestizo) pigs or whether the piglet offered for sale is an original native pig.
They would even go to the extent of buying only native pigs that are wholly black, with no other color like white on the piglet. This is attached to their cultural value.
Only when the buyer is satisfied that the piglet is considered an original native pig, then a deal is struck and purchase is consummated.
In fact there are traditions in CAR particularly on sacred offerings whereby in the butchering of pigs, only black native pigs are utilized. Even a native pig with white patches in it is not allowed by elders in the conduct of their tradition.
Such a tradition is often observed in the eastern and western portions of the provinces in CAR.
Or, as a result of the DNA finding, pigs found in Ifugao and Kalinga or elsewhere in Cordillera highlands may have a separate origin from other Asian pig breeds.
Such startling finding has galvanized the researchers to suggest that further studies on the pig subpopulation in Northern Luzon are essential for the improvement and conservation of “economically important native animals.”
A DNA test is often elevated as a 99.999 per cent finding and is, or at the most, accepted by Philippine courts for it veracity.
For future studies, the UP researchers suggested that pigs from different provinces should be sampled and analyzed, to complete the evolutionary history of Philippine pigs.
Furthermore, since the research utilized a “maternally inherited molecular marker,” the possibility of paternal admixture by wild pigs into the Philippine pig populations cannot be discounted, the researchers revealed.
For one, the researchers said, most rural people in the olden days in the study sites practiced free-range care of their pigs where these animals root out for food, where wild male pigs got in contact with the domesticated rooting pigs and eventually bred them, the researchers explained.