We have just made some updates to the deCODEme ancestry service. Now you have more power and flexibility when you compare your genome with that of friends or individuals from different populations around the world.

Your genome can be viewed as a mosaic or tapestry made up of fragments of chromosomes from your ancestors. Fragments of chromosomes inherited from very recent ancestors, say grandparents, are expected to be large – typically tens of millions of nucleotides in size. As ancestors become more ancient, then the size of the chromosome fragments inherited from them become smaller – down to a few thousand or hundred nucleotides for ancestors born thousands of years ago.

Our new and improved genome comparison tool enables to you compare your genome with another individual in order to determine which chromosome fragments you share and to see how much of your genome is shared. The fascinating thing about this analysis is that each shared fragment represents a common ancestor. The number of shared fragments and their size reflects the number of common ancestors and how far back in time they are found. In other words, you can see how closely you are related.

When genomes are compared, your chromosomes are broken down into fragments of a particular size and sharing is evaluated for each fragment. Before the fragment size was fixed at 1 million nucleotides. Now you can change the size of fragments that are compared, from a minimum of 250 thousand nucleotides (250Kb) to a maximum of 20 million nucleotides (20Mb). The minimum fragment size will reveal shared chromosome fragments from common ancestors going back thousands of years. The maximum fragment size will reveal only shared chromosome fragments from very recent common ancestors – i.e. going back only a few generations. Setting the fragment size thus lets you select how far back in time you want to hunt for common ancestors.

This image shows results of a comparison between an Icelander and an Orkney Islander using a fragment size of 3Mb. The brown lines are shared fragments, inherited from common ancestors from more than 1000 years ago!

We at deCODEme just wanted to let you know that we have added a Forum where you can discuss genetics, ancestry and health. Our experts are looking forward to your questions and comments so we hope you take advantage of this new feature.

We are constantly working on making deCODEme more valuable and informative and we appreciate your continued interest.

We hope you have a pleasant and festive holiday.

The deCODEme Team

The deCODEme team has been busy working to update and improve your deCODEme experience.  Additions include ABO blood types, Kidney stones, Eye color and Statin-induced myopathy. We have also added  a section for feedback and research and a more detailed Male line analysis.

Here is a summary of the additions and changes:

FEEDBACK AND RESEARCH

Many deCODEme customers have contacted us, asking whether they could contribute to our research efforts and receive statistical feedback about the deCODEme user community. In response to these wishes, we have introduced optional survey questions about the various traits included in the deCODEme scans. To see the entire list of questions, click the “Feedback and Research” link on the home page that appears when you first log into your deCODEme account. Alternatively, you can see the questions for each trait when you view your results by clicking on the new “Research” tab. Participation is optional and entirely voluntary and you can, at any time, have the questions removed from your account by checking the box marked “I do not want to participate in feedback & research”.

Updates for deCODEme Complete Scan

ANCESTRY UPDATES

A new look for the Female Line and Male line ancestry analyses
The deCODEme web-design and ancestry teams have made several changes to the look and feel of the Female Line and Male Line ancestry analyses. Our aim was not only to make the presentation of your results clearer and more visually pleasing, but also to accommodate new features, some of which have already been introduced (link to More detailed Male Line analysis).

More detailed Male Line analysis
The deCODEme ancestry team has recently updated and expanded the classification of Y-chromosomes in the Male Line analysis. We have added two new Y-groups to our Male Line classification system, bringing the number Y-groups to 24. More importantly, male deCODEme customers can now have their Y-chromosomes classified into one of over 105 Y-subgroups. This provides a much more detailed picture of your genealogical relationship to other people through the male line. Thus, for example, if your Male Line result previously assigned you to Y-group R1b, you can now find out which of the 15 different R1b subgroups you belong to. You are much more closely related to other members of your subgroup through the male line than you are to those who do not belong to that subgroup – even if they belong to the same Y-group as you. Click on the “subgroup tree” tab on your Male Line results page to learn more about your Y subgroup.

HEALTH WATCH UPDATES

New diseases and traits in Health watch

Kidney stones
Kidney stones are small crystals formed of dissolved minerals, mainly calcium, that form in the kidneys. Smaller stones can simply be passed through urination, though larger ones can block the urinary tract, causing considerable pain and bleeding. Kidney stones affect some 5% of women and 10% of men in the industrialized world. We are proud to announce that our scientists at deCODE genetics have just published new scientific results that shed light on genetic variants that affect the risk of developing kidney stones. Within hours of the first report of this exciting new discovery in the scientific literature [link to manuscript on Nature genetics website], deCODEme customers can log into their Complete Scan accounts and examine an estimate of their genetic risk for developing kidney stones! The discovery involves a common genetic variant in the CLDN14 gene on chromosome 21 that is associated with increased concentration of urinary calcium, which in turn leads to an increased risk of developing kidney stones.

ABO blood types
There are four different ABO blood types, named A, B, O and AB. Many people know their ABO blood types, because they are typically assessed by healthcare workers when a person receives blood or donates blood or an organ. This is because it is critically important to match ABO blood types of donors and recipients of blood or organs. Your ABO blood type depends on which kind of glycoprotein or antigen is found on the outside of your blood cells. These glycoproteins come in three forms and are referred to as A, B and O. The gene that determines your ABO blood type is found on chromosome 9 and is called ABO glycosyltransferase. In the simplest terms, this gene may be said to come in three different forms, that is, it has three different alleles. These alleles are also named A, B and O, because each is responsible for the production of its namesake glycoprotein (antigen). It is therefore the combination of alleles that you inherited from your parents that determines which glycoproteins are found on your blood cells and thereby your ABO blood type. The deCODEme genetic scan determines which combination of the three ABO alleles you carry on chromosome 9 and therefore which blood type you are likely to have.

Eye color
Eye color refers to the color of the iris. The color of the iris is determined by the amount and distribution of melanin, a dark brown pigment, which is produced by a special type of cell called the melanocyte. In simple terms, a brown iris contains abundant melanin, whereas a blue iris contains much less melanin. Albinos have an almost complete lack of melanin, resulting in a red or pink iris color (due to the greater visibility of blood vessels through the almost transparent iris). The vast majority of people in the world have brown eyes. It is primarily those of European descent that we find normal variation in eye color, in the form of blue, grey or green colored eyes. While eye color is a trait determined by several genes, some genes seem to play a more important role than others. The deCODEme Genetic Scan identifies a genetic variant associated with blue and brown eye-color in the HERC2 gene on chromosome 15. The results provide an interpretation of the associated likelihood of blue/grey or brown eye color in individuals of European descent.

Statin-induced myopathy
Statins are a group of compounds that are commonly prescribed by physicians for individuals with high cholesterol to reduce risk of cardiovascular diseases. While statins are generally safe and effective, there are some known side-effects. One that affects a minority of those taking statins is a muscle disease called statin-induced myopathy, the symptoms of which include muscle pain and weakness.

As always, we welcome your comments and suggestions and encourage you to visit your deCODEme account frequently to take advantage of regular updates and new features.

The Map of Kinship can be used not only to learn about your relationship to people from the different continents, but also your relationship to populations within the continents.

From a genetic point of view we are all unique, but some individuals are more similar than others. Generally speaking, genetic differences reflect geography. People from the same geographic area tend to be more genetically similar than people from distant parts of the world. This means that the greater your genetic similarity is to a particular population, the more likely you have ancestors that belonged to that group in the past and relatives in the present.

The deCODEme team has recently implemented a new tool, called the Map of Kinship. This tool can be used to explore a person’s ancestry and genealogical relationship to more than 1000 individuals from 53 populations from all over the world.

Map of Kinship rotates in 3D

This tool is based on a powerful statistical method, called principal components analysis, which is used to uncover the hidden patterns of genetic variation that can tell us how closely people are related. Such patterns are of great interest from a historical point of view, as they are the result of thousands of years of migration, from time humans first appeared about 200 thousand years ago and to the present.

In the Map of Kinship, what you see is like a conventional map. However, instead of cities or towns separated by geographical distances, you see the genetic distances between yourself and people from 53 different populations from all the different regions of the world. People from the same population tend to form tight clusters on the Map of Kinship. Likewise, populations from the same regions of the world also tend to cluster together on the map. Your position on the map tells you how closely related you are to the individuals and populations that are shown. The Map of Kinship can be used not only to learn about your relationship to people from the different continents, but also your relationship to populations within the continents. Thus, for example, it can tell you whether your ancestors were mostly from Europe, Africa, Asia or the Americas. If you are most similar to Europeans, then the Map of Kinship will reveal whether your
ancestors were mostly, for example, Scandinavian, Italian, Russian or from the Middle East. If your friends or family have bought a Complete Scan from deCODEme, then you can also see where they fit into your Map of Kinship.

Iceland was mainly settled by Scandinavian men and women from Irealand and Scotland

In a paper published today scientists at deCODE genetics present the results of the largest study of ancient DNA from a single population ever undertaken. Analyzing mitochondrial DNA, which is passed from mother to offspring, from 68 skeletal remains from approximately 1000 years ago, the study provides the most detailed look to date at how a contemporary population differs from that of its ancestors. The results confirm previous deCODE work that used genetics to test the history of Iceland as recorded in the sagas.

Audio link:  Dr. Kari Stefansson interviewed on BBC WORLD. BBC

These studies demonstrated that the country seems indeed to have been settled by men from Scandinavia – the vikings – but that the majority of the original female inhabitants were from the coastal regions of Scotland and Ireland, areas that regularly suffered raids by vikings in the years around the settlement of Iceland 1100 years ago.

Perhaps the most remarkable finding of the study published today is that the gene pool of contemporary Icelanders appears to have evolved rapidly over the intervening thousand years. As a result, the original female settlers are genetically more closely related to the present day populations of Scotland, Ireland and Scandinavia, as well as those of northwestern Europe and even southwestern Europe, than they are to present day Icelanders. This is an important demonstration of a phenomenon known as ‘genetic drift.’ In essence, in any population certain individuals will have more offspring and, by chance and in this case over the course of 35 generations, many more descendants than others. And as a result, particularly in a small population, the genetic variety of the original population can decrease and change over time. In this study only mitochondrial DNA was studied, but the same phenomenon applies to the Y chromosome, which is passed from fathers to sons, and to any other part of the genome. The paper, ‘Sequences from first settlers reveal rapid evolution in Icelandic mtDNA pool,’ is published today in the open-access journal PLOS Genetics.

“This study is a major contribution to the use of ancient DNA studies in tracing the history not just of single populations, but of our species and how we spread from Africa to every corner of the globe. It is the first such study to be large enough to permit meaningful statistical methods to be applied to ancient DNA. We very much hope this will aid and encourage others to follow with large studies in other parts of the world. In this field, as in the genetics of common diseases, we are pleased and proud to be able to put the knowledge we gain in Iceland to work for the benefit of people everywhere,” said Kari Stefansson, CEO of deCODE.