Clearly the Finns were an exceptional bunch, wedged at the top of the world between Sweden and Russia and speaking an odd tongue that is unrelated to other languages of Scandinavia.
Does all of this make Finns a race? Race is used in biology for birds and animals — the term is tantamount to subspecies — but her studies had no use for it. Patterns of human variation can be linked to geography, and geographic ancestry can be linked to health risks. As a genetic explorer Peltonen has followed the movement of populations in history, knowing that genes had diversified during the moves, but in Finland as elsewhere only a tiny fraction of the alleles and health risks are distinctive.
The story of these genes helps us visualize how Finland was settled. By convention the Finns are white or Caucasian. Peltonen was probably the palest person on Westwood Boulevard.
Nevertheless, in the 19th century she would have been classed with the Mongol race because anthropologists of that day lumped Finns with the Laplanders, or Sami, as they call themselves — the nomadic, faintly Asiatic people who roam the Scandinavian Arctic.
Congenital nephrosis is a deadly kidney disease that crops up in Finland. To become ill, the patients had to inherit a gene variant from both parents. When geneticists traced their pedigrees back nine generations, they found that the parents of the patients were related through three individuals.
Many grandparents of patients with congenital nephrosis lived in areas of Finland that were only sparsely settled after , which made intermarriage among relatives more likely. Finland is a land of lakes and forests and rushing wind. Helsinki, the capital, on the southern coast, lies on the same latitude as Anchorage, Alaska. Finland extends as far north as Alaska, but the influence of the Gulf Stream makes Finland milder. Helsinki is not too different in appearance from other great cities of Europe.
Its pool of DNA must be the most heterogeneous in Finland because Helsinki is a crossroads, past and present, to and from other peoples of Europe. About 10, years ago, after the glaciers of the Ice Age retreated from the Scandinavian landmass, bands of hunters and fishers moved across the Baltic Sea and into the Finnish wilderness. Where in Europe these early settlers came from is debated. Blood-typing and genetic analysis link the Finns with other European groups, with maybe a bit of Laplander thrown in.
Most population geneticists agree that the main migratory stem, well before the budding of the Finns, has its roots in Africa. They also agree, if with less unanimity, that the most common genetic variants found in contemporary human beings are ancient in origin — at least 50, years old.
These are called complex conditions because their genetic and environmental causes are multiple and murky. Two thousand years ago farmers inhabited the southern and western coasts of Finland. Then, as now, meat and dairy foods were the mainstays of the diet, all the more so in a land where raising crops was hit-or-miss. Then, as now, a minority of Finns would have trouble digesting the milk and cheese because of a gastrointestinal condition known as lactose intolerance.
Lactose intolerance occurs in populations around the world. In Asia and Africa rates are as high as 80 percent. The most frequent form of the disorder develops in adulthood. In the late s Leena Peltonen and her team, capitalizing on Finnish homogeneity, unlocked the key to the condition. They found that a tiny change in the sequence of DNA, a change of a single letter, from a C to a T, causes the gene to lose its capacity to make the enzyme.
Peltonen found the identical alteration in groups and races who by geography were far apart. That finding suggested that the allele occurred before human populations branched out from Africa.
Adult lactose intolerance appears to have been the normal condition for Homo sapiens , years ago. Initially the people who drank milk from cows had something unusual about them, but by chance the new allele improved the welfare of human beings on their way north. The gene helped a pale-skinned strain of farmers adapt to the European winter, when agriculture failed.
Peltonen likes this story because it shows how DNA drawn from a small corner of the world contains a message of universal significance. The alleles for lactose intolerance and lactose tolerance represent time-tested genes of the human race, just the opposite of the alleles of the Finnish Disease Heritage, which are native born and recent. During the s about , Finns inhabited the coastal zone of what was then Swedish territory.
Concerned about the unguarded border with Russia, King Gustav of Sweden induced Finns to migrate north and east into the pine forest. After the colonists established small farms and villages along the eastern frontier, immigration stopped, and the region remained isolated from the rest of Finland for centuries.
With an initial population in the several hundreds, the situation was ideal for what geneticists call genetic drift and founder effects. Mutations that were too scarce to make a dent on a larger population were enriched in the small but expanding group of people in East Finland.
Most of the disorders that transpired were recessive, meaning that two copies of a flawed gene had to be inherited, one from each parent. Although people did avoid marrying their relatives, after 5 to 10 generations it was almost impossible that bloodlines would not have crossed in spouses from the same area. From Helsinki to the Kainuu district in East Finland the distance is some miles, pleasantly covered on smooth highways.
In the last half of the journey the road passes banks of purple lupine, thick stands of conifer and birch, big clean lakes with a cottage or two on the shore, fields with little hay sheds in the center, then more woods and more lakes and more fields. The landscape, like the DNA, is homogeneous. The only exclamation points are the tall steeples of the churches, one for each widely spaced town.
In later generations, when a child received a copy of the gene from each parent, it seeded a disease called Northern epilepsy. When Aune Hirvasniemi, a pediatric neurologist at the local hospital, began to track the disease in the late s, she found 19 patients in a handful of families.
No one had connected the cases before. Hirvasniemi consulted the records of the Lutheran Church, which for years had written down the comings and goings of Finns in each parish.
Creating a medical pedigree for Northern epilepsy, she followed it all the way back to its founder, Matti. She published her discovery of the epilepsy in , the same year that researchers in Finland identified its gene on chromosome 8. Hirvasniemi is a smiling woman with penetrating blue eyes. She had not heard of any new cases of Northern epilepsy in more than a decade, which she believed was partly because Finns now migrate out of Kainuu, an economically depressed region. At least half the hay sheds in the fields are abandoned and crumbling.
About one in seven Finns is a carrier of at least one of the special disorders. Partly because of genetic counseling, but mainly because of luck, only 10 newborns a year are stricken with the distinctive conditions.
Norio, a medical geneticist, was an early investigator of the disease heritage. In the late s he was a pediatrician like Hirvasniemi and curious about a lethal kidney condition that he named congenital nephrotic syndrome.
Traveling around the country, Norio deduced its genealogy from family accounts and church records. Afterward he became a genetics counselor in Helsinki.
Other people might feel stigmatized by an unusual genetic heritage, but Finns take pride in it. That is something of a psychological turnabout. Like many people identified as belonging to a racial group, Finns used to be defensive about their biological identity, which was disparaged by their domineering neighbors.
Today speaking about races is genetically out of date. Norio refused even to entertain the notion that Finns could be called a race of people because of their genetic idiosyncrasies. A paper they published in the journal Science several months ago has gotten a lot of attention, because after detecting a suspect allele in Finnish families with asthma, the researchers found the same gene in families with asthma in Quebec.
Even more interesting, the allele is a variant of a gene that might actually be part of the disease process. In exploring complex disorders like asthma, diabetes, cancer, and heart disease, scientists can find genes that are associated with the condition: Such and such a gene is plucked out by computer analysis on the basis of its frequency.
The asthma gene found by Kere and his colleagues — which they immediately patented — is different because it expresses in bronchial tissue, where drugs might reach it.
Investors and pharmaceutical companies noticed because asthma medications are a big business. With funding from foreign backers and the Finnish government, the scientists formed a small company, GeneOS, in Helsinki, where they are working on how the gene and its protein work. It was pure frozen DNA — concentrated copies of the Kainuu asthma gene. Laitinen pointed out yet another advantage of doing science in Finland.
The same supermarkets are everywhere. In health care, people are treated the same everywhere. But Finland is a good place for medical research because people feel positive about it. So as a scientist I value the environment of Finland more than the genes. For 10 years Tuomilehto has collaborated with American investigators at the University of Southern California and the University of Michigan on a gene-mapping project for type 2 diabetes, formerly known as adult-onset diabetes.
Patients have numerous health problems because their blood-sugar levels are too high. Many eventually need insulin shots, like the children and young people who have the harsher type 1 diabetes. In most other countries the records are lousy if you want to trace back relatives. On my computer I can get, with the permissions that I have for each patient, the records on all past diagnoses, all hospitalizations and prescriptions.
Also socioeconomic information like taxable income, ownership of a car, education, and marital status. Nonetheless, because diabetes is an extremely complicated disease, the results have been disappointing. In other words, type 2 diabetes could never make it into the Finnish Disease Heritage, where a change in a single gene is decisive. Given that the gene variants for diabetes may remain elusive for a while, Tuomilehto has concentrated on the environmental aspects of the disease.
Obesity, he pointed out, is the leading risk factor for the condition. Genes interact with the environment. According to this view, whenever susceptible genes meet too many calories, weight goes up and diabetes follows. That might help explain the postcard Tuomilehto has pinned to the wall behind his desk. It shows an enormous young man lying on his side on a beach. When Finns brood over their history, their dark thoughts turn east, to the monolith of Russia.
Europeans can be divided into two groups based on an analysis of protein-coding genetic variations — into Finns and non-Finns, reports Nature. The University of Eastern Finland summarises the findings of the research project on its website by estimating that in comparison to other Europeans, Finns are so distinctive in terms of their genotype that they should be classified as a population group of their own.
The study analysed variations in the exome, or protein-coding, genome sequences of more than 60, individuals in Africa, Europe, North and South America, and East and South Asia in an attempt to identify mutational recurrences in different ethnic groups. Analysing the genotype of Finns was not an objective of the research project, reveals Markku Laakso, a leading researcher into the genetics of type 2 diabetes and one of the co-authors of the study. Finland, he adds, stood out in the analysis to the surprise of the researchers.
But Finns are also Asians as they really don't resemble anyone [ Finns have a unique genetic ancestry particularly due to two factors, according to Nature.
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