OriginsBy Michael L. Tan
Philippine Daily Inquirer
The front-page article “Who is the Filipino? genome expert asks” (Inquirer, 2/18/13) got me several text and e-mail messages asking for my opinion, as an anthropologist, about the prospects of finding ourselves in our genes.
As a cultural anthropologist, I will have to say being Filipino has little to do with our genes or biology. “Filipino” is a term created only in recent history, first used by Spaniards born in the Philippines, and then later taken over by Rizal and other reformists. Today, “Filipino” can mean a legal identity, as in citizenship, as well as a cultural identity, being Filipino. One can be a Filipino citizen and yet have little sense of being Filipino, and one can be a non-Filipino citizen and yet be Filipino in outlook. As for the genes, well, hypothetically anyone, regardless of genetic makeup, can become Filipino, legally or culturally.
Genes and medicine
As a biological anthropologist, though, I agree it is worth unraveling human genes in the Philippines. As a medical anthropologist, I agree with Michael Purugganan, the geneticist interviewed for that article, on the idea of looking at what our genetic susceptibilities are, as well as various defenses that we have developed in response to challenges in our environment. For example, a certain percentage of Filipinos have glucose-6-phosphate dehydrogenase (G6PD) deficiency, a genetic disease that causes damage to red blood cells and anemia when the person is exposed to certain chemicals in food and medicines. G6PD is one of the genetic conditions that can be detected through our newborn genetic screening program.
But G6PD is not a uniquely Filipino disease, and in the Philippines it has higher incidence in areas like the Cordillera because it gives people a certain degree of protection from malaria, a disease which is endemic in that region. This is natural selection at work, individuals with G6PD having higher chances of survival in a place with a high incidence of malaria.
There are thousands of other genetic conditions that can and should be studied, some with serious implications like G6PD and others that are almost trivial, but still interesting. When I see people drinking and turning red with the first swig of beer, I think immediately, “Asian flush” or “Asian glow” or “alcohol flush reaction,” which happens because of a genetic condition where the individual breaks down alcohol very rapidly, and shows effects like the skin flushing. The condition is more common among Asian populations than European and African ones, and it certainly is widespread in the Philippines, with friends of such “victims” teasing them: “Nakaapak lang ng tansan, lasing na kaagad.” (They just step on the beer bottle cap and they’re drunk.)
The origins of Asian flush are still not clearly understood, but one theory is that the condition gives people some protection from dreaded amoebic infections. So there. If you have the condition, boast of having that Asian glow, and some resistance to amoeba.
Medicine is said to be the youngest science, and genetics the youngest of medical fields. The mysteries of DNA, our genetic building blocks, were discovered only 60 years ago, and the human genome project mapping out our genes was completed only in 2003.
Advances in genetic research have been rapid, which is why people sometimes have unduly high expectations of this science, especially to help us understand ourselves. It’s not surprising that we look to genetics as well as part of our search for the Filipino, for ourselves, and sometimes we become unrealistic, such as expecting genetics to explain why we have corruption.
What genetics can do is help explain “what we are” in terms of the chaotic mixing of gene pools. You’ll notice I’ve been using terms like “populations” and “gene pools,” and avoiding “race.” The reason here is that “race,” including the local term “lahi,” does not actually exist. The American Anthropology Association issued a statement rejecting the concept of “race” in 1998:
“Evidence from the analysis of genetics (e.g., DNA) indicates that most physical variation, about 94 percent, lies within so-called racial groups. Conventional geographic ‘racial’ groupings differ from one another only in about 6 percent of their genes. This means that there is greater variation within ‘racial’ groups than between them.”
It’s fine to be curious about our origins, but we have to be careful about our yearning for a kind of “racial accounting.” Many years ago I wrote about the Filipino fixation on race and percentages, with people constantly asking me if I’m “pure” Chinese and if not, what percentage Chinese I am. Sometimes I want to answer, tongue in cheek, that I’m quite certain about my state of purity when it comes to thoughts and deeds, but will never dare to say I’m sure about my genetic purity, or its lack thereof. It’s not just because of the difficulty of tracing ancestors but of recognizing that Homo sapiens is the product of many generations of interbreeding.
But yes, it can be exciting to look at the meeting of people from different gene pools that has taken place to produce the population we have today in the Philippines. Even without fancy equipment, we can do a bit of detective work, going back in time to trace what’s called gene flow and the population in the Philippines.
Gene flow is a biological term used to refer to the way genes move from one place to another. For human gene flow, we’re talking about people moving from one place to another and mating.
You can imagine what gene flow is like right now for our population, with some 10 million Filipinos living and working overseas. We’re already seeing all kinds of mestizo Filipinos in our midst—the product of migration and gene flow. Those who come back and settle down in the Philippines, becoming celebrities and football players, for example, will contribute to the gene flow if they have children here, reconfiguring the gene pool in the Philippines. Conversely, those who stay overseas will also modify the gene pools there. The United States is an example—a melting pot where all kinds of gene pools have converged, including contributions from Filipino migrants.
Gene flow is not a product of our times alone. In the Philippines trade and colonialism over the last 2,000 years or so meant intensive gene flow, too, with people coming from all over the world and leaving their genetic footprints here. We think of “outside” genes mainly as those of the Chinese and the Spaniards, but in the second part of this column, I’m going to explain that those terms are not accurate from the viewpoint of genetics.
I’ll take you back in time, a few hundred thousand years, to look at the studies that do offer us tantalizing glimpses into our origins, going beyond racial accounting.
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