With a history of colonialism and mass migration events from different corners of the world like Spain, China, and the myriad of Malayan islands, the Philippines is one of the most diverse melting pots in the world. The archipelago has been a crossroads of culture and trade for centuries, with different ethnic groups and nationalities intermingling and intermarrying leading to a unique gene pool. Suffice to say, this has created unique sets of haplotypes found in the country that link individuals to certain conditions, risks, or even reveal historical migration patterns and relations—but first things first, what exactly are haplotypes?

 

Haplotypes are defined as a set of genetic markers that are inherited together on the same chromosome from a parent. These genetic markers can include small deviations of DNA (nucleotide) bases called single nucleotide polymorphisms or even large structural differences like longer stretches of varying DNA sequences (Variable Number Tandem Repeats) and mutations like deletions and insertions. 

 

The fact is, even a small alteration in a person’s DNA sequence can lead to variation in a person’s trait—and most of us, barring identical twins, have large spans of differing DNA sequences that make us, us. Added to our own unique circumstances of environment that affects our very genes and how they react, people as individuals are made. 

 

Nonetheless, this does not discount the fact that our genes came from our parents, and theirs from their parents, and so on, and so forth. Also considering the fact that Homo sapiens share 99.9% of DNA that makes them human in the first place, people share a majority of their DNA with each other, even more so if they come from a particular ethno-linguistic group (people who share common ancestry, language, and cultural identity).

 

The most common haplotypes in the Philippines include haplogroup O1a-M119 and haplogroup O2a1-M50. The former is actually found in many Southeast Asian populations with Austronesian ancestry spanning from several polynesian cultures like the Māori, Samoans, Malaysian, and Indonesians. On the other hand, the latter refers to Filipino populations who are of Han Chinese ancestry and are a result of mass Chinese immigration during the Spanish colonization of the islands between the 16th and 19th centuries for trade. 

 

Other haplotypes include haplogroup R9a (Filipino-Indian ancestry), haplogroup E1b1b1a1b-V13 (Filipino-European ancestry with links to Austronesian migration), and the indigenous haplogroup C1b2 (found in the  Cordillera region of Luzon).

 

While haplotypes are a fascinating method to trace the country’s human evolutionary history, it is also typically used for the tracking of genetic diseases at the family or population level.  In fact, particular haplotypes are known to be associated with higher risks of certain diseases. For the O1a-M119 haplotype, conditions like Thrombocytopenia (low platelet count and increased bleeding and bruising) along with congenital heart disease are common. Meanwhile, the O2a1-M50 haplotype is associated with Osteoporosis (fragile and brittle bones) and Type 2 diabetes are prevalent (insulin insensitivity), among other things. 

 

However, it is important to note that while haplotypes may  increase the risk of certain conditions, they do not cause them directly, as multiple genetic and environmental factors can also play a role in the development of these conditions.

 

Nevertheless, genetic diversity and the myriad of haplotypes of the Filipino people provide a compelling narrative of our past, present, and future, whether it be in terms of our ancestry, human evolution, or genetic predisposition for certain traits or diseases.