Haplogroup I2B1C

Our Brewer HaploGroup I2b1c

Our Brewer family ancestral Haplogroup descendancy


    A haplogroup is defined as the group of all the male descendants of the single person who first showed a specific rare mutation on the Y-chromosome called a Single Nucleotide Polymorphism (SNP, pronounced snip) which may occur once in a period of tens of thousands of years. Haplogroups represent branches of a genetic tree for Homo Sapiens and every male in the world can be located on one branch or another based upon the specific Y-chromosome mutation he carries. The major branches of the Y-DNA tree of Homo Sapiens are labeled A through R. These major branches have additional branches where a haplogroup is broken down into sub-haplogroups.  SNP tests taken to determine the haplogroup of the descendants of Johannes Brouwer show that the Elias Brouwer and John Brewer lines belong to the haplogroup now designated I2b1c, in particular haplogroup I, subgroup 2-b, clade 1c. NOTE: the subgroup 2-b designation was adopted by the Y-Chromosome Consortium (YCC) in May 2008. It was previously designated as 1-c.  In 2008. Researchers led by Dr. Hammer published an updated Y-chromosome haplogroup tree in “Genome Research” and in May 2008 Family Tree DNA adopted the updated nomenclature of that publication. While the name of the haplogroup branches changed, and will continue to change as new branches are discovered, the test results and interpretation remain the same. Further information may be found at


Sept 8, 2010:   I2b1 has been further subdivided into 5 subgroups, one of which is I2b1c

The Haplogroup  of the Jan Brouwer descendants is I2b1c based on being positive for SNP P78.  Further, the 67 marker Y-DNA test results show the Jan Brouwer descendants have a unique and very rare allele value of 7 at STR DYS565. Typical values are 9 to 14, the value of 7 only occurs in about 0.01% of the population and defines the Family branch of Jan Brouwer within the general I2b1c clade. For further detail on this unique allele value click here.   I2b1c  has the highest frequency in Germany, Netherlands, Denmark and England. The distributions of haplogroup I2b1 comprises less than 10% of the total Y-Chromosome diversity of all populations outside of Lower Saxony and seems to correlate fairly well with the extent of the historical influence of the Germanic peoples, being found in over 4% of the population in Germany, the Netherlands, Belgium and Denmark.


Sequence of SNP mutations that define our Haplogroup I-2b, and their date of occurrence:



M168 (C->T)  60, 000 ya ( years ago) out of North Africa->Middle East

            Defines the common ancestor of every non-African person

    -> M89 (C->T) defines Super Haplogroup F, 45, 000 years ago, origin Middle East

                represents 90-95% of all non-African populations

        -> M170 (A->C), defines Haplogroup I, 22, 000 years ago, origin Europe

                    During the Gravettien  and Solutreen age

            -> P38  defines HgI-2   followed by our specific Brewer family mutation,

                -> M223 (C->T) defines  HgI-2b, 15, 000 years ago, origin S. France

                    During the Magdalenian Age

HgI-2b today:  principle locations -- Netherlands, N. Germany, S. Scandinavia.

        principle languages -- Germanic (Dutch, German, English, Scandinavian)


    Population genetics provides the means to read a record of ancient human migrations in the DNA of living people. The human genetic code, responsible for features such as eye color, hair type, etc., also contains stretches of code with no apparent function at all. Once in many thousands of years, a harmless SNP mutation can occur in one of those functionless stretches which is then passed down to all of that person’s descendants. Generations later, finding that same mutation, or marker, in two people’s DNA indicates that they share the same ancestor.  By comparing markers in many different populations, it is possible to trace their ancestral connections and discern when and where different groups of people seperated as they migrated around the world.  This is a project goal of the current Genographic project headed by Dr. Spenser Wells, and one that you may participate in as a member of the Brewer surname project at FTDNA.  More information about the Genographic project and how to join can be found at www.familytreedna.com/ftdna_genographic.html


Our “Deep Time” Genetic Journey:

    Our own male line of ancestors (some 700 generations of descendants of the genetic founder of our haplogroup) goes back 15, 000 years from the present to our prehistoric origins in a cave in southern France during the Last Ice Age.  There, we discover our family “Adam,” the individual who was first marked with a Y-chromosome mutation called M223 and who founded the northwestern European population group designated Haplogroup I-2b.


    The genetic mutation at marker M223 that defines our haplogroup I-2b is the latest mutation in a genetic journey that began with one of the earliest mutations 60,000 years ago when, in one individual, the common ancestor of every non-African person in the world, a random DNA transcription error occurred at a location on the Y-chromosome called M168.  We Brewer family males, in common with all non-Africans, now carry that mutation at that specific location in our DNA.  Similarly, 45,000 years ago, a new mutation occurred in an ancestor in the Middle East which is designated M89 and which marks about 90-95% of all non African populations. Another mutation, designated M170, occurred 22,000 years ago in an individual in Europe and the descendants of that man are now grouped into what is called Haplogroup I.  Then, 15,000 years ago in southern France, our Brewer ancestor passed on a SNP mutation called M223, forming a subgroup within the Haplogroup I called 2-b.  We male Brewers in the Johannes Brouwer family lines now carry all the above markers, and so, according to the current (2008) classification adopted by the Y-Chromosome Consortium (YCC), we are assigned to Haplogroup I-2b  -- which lineage, as mentioned earlier, is believed to have its roots in southern France.  Today it is found most frequently within Viking/Scandinavian populations in Northwestern coastal Europe, principally in the Netherlands and northern Germany.


    When the modern humans from whom we descend migrated north from the Middle East and were replacing Neanderthals, the continent was significantly colder than it is today. Around 29, 000 years ago the last Ice Age began and the weather became even colder with glaciers pushing south until they were within a few hundred miles of today’s Amsterdam, Moscow, and Stonehenge.  At the height of the last Ice Age, between 20, 000 and 16, 000 years ago, modern humans were forced to leave northern Europe, abandoning what is now Britain, northern France, the Low Countries (i.e. Netherlands), and Germany. These proto-Europeans retreated to warmer areas in southern France and Spain around the Pyrenees and to the Balkans north of the Black Sea.  All human habitation ceased above the line of the Last Glacial Maximum (LGM). Then, about 14, 000 years ago, as the Ice Age ended and the ice began to retreat, resettlement resumed and the survivors of the glacial period, including our direct paternal ancestors, slowly moved back into northern Europe, reclaiming the areas we call the Netherlands, England and northern Germany.


    Some 15,000 years ago, about 1,000 years prior to the end of the Ice Age and resettlement, our paternal ancestor became the first male to carry a mutation in the nucleotide sequence of his Y-chromosome, known today as marker M223 where, during the transcription of the Y-DNA code, there was a substitution of a “T” (thymine) where previously there had been a “C” (cytosine).  It was a mutation that would not have any physical consequence for the boy, but it would mark him and his male descendants forever as a special group; diverging from the genetic signature we call M170, or Haplogroup I, carried by his father and his earlier paleolithic European-specific ancestors by the addition of this new marker.  The descendants of this boy increased in number until they would eventually come to represent 18% of today’s total European Gene pool, forming the group to whom we give the designation Haplogroup I-2b.  It is from this boy, the originator of the M223 genetic marker mutation, that our Brewer paternal family line traces its specific lineage.


     Of the three main areas of refuge from the Last Glacial expansion, two of them recolonized the nordic populations of Scandinavia -- which, as mentioned above was completely depopulated during the last Ice Age:

    1) the Iberian Peninsula/southern France (which was the source locale of our male founder of the M223/Hg I-2b subgroup, as well as a later branch designated M253/Hg I-1b), and

    2) the Ukraine/Central Russian Plain (who also represent the M253/Hg I-1b subgroup ).  A third group comprised the P37/HgI-2a subgroup, which, isolated from the others, persisted in the area of present-day Austria, the Czech Republic, and the northern Balkans.


About our early European ancestors

    We do not know what language our subgroup founder spoke but his early ancestors, 26, 000 years ago, spoke a proto-Indo European language representative of the Gravettian culture that had spread across Europe from the river Don in Western Russia. When the Glacial Maximum forced his European hunter forefathers into the geographically separate refuges, the isolation and increased local interaction gave rise to the emergence of the three Indo-European language families in Western Europe -- Italic (including today’s Italian, French, Spanish and Portuguese), Germanic (including English, Dutch, German and Scandinavian languages), and Celtic.  By the time of our M223 mutation, between 16, 000 and 14, 000 years ago, both the HgI-2a and HgI-2b haplogroups migrating north from southern France apparently spoke an early form of Germanic language which they carried to the areas of England, Germany, and southern Scandinavia. Many of the ancient river names of Germany, France, and England -- such as "Rhine," "Rhone," and "Thames" -- appear to arise from a common system of naming, and although these names are Celtic in form, they do not appear to be Celtic in origin. There has been a great deal of lively argument as to what this "Old European" language might have been, but it is widely accepted that it was Indo-European and most likely an early form of Germanic. These Haplogroup I subgroups played a central role in the process of human recolonization of Europe from the isolated refuge areas. The first to repopulate the northern European plains were Magdalenian [Note 1]  reindeer hunters from southern France. The Brewer family haplogroup I-2b formed a part of the Magdalenian population.  They developed new technologies, such as spear throwers around 14, 000 years ago and by that time they had reached England (which was then attached to the continent, due to lowered sea levels), the Netherlands, and Germany.  A thousand years later, they had also pushed north into Denmark and southern Sweden and east as far as Poland and southern Lithuania .[Note 2]


    The clan, or community into which our M223 “Adam” was born, probably consisted of between 20 to 50 people at most, and the population density at that time was on the order of one person per 15-50 square kilometers, no more.  This means that each community in the refuge areas controlled and hunted in an area between 750 to 2,500 square kilometers. Even though this is a sparse density in today’s terms, it represented a period of far more social crowding than before and the result was one of great innovation, as we have seen.  In spite of the slow reproductive start, we have noted above that our ancestor’s offspring would eventually produce a family line that was responsible for 18% of northwestern Europe’s population, in particular the Netherlands, northern Germany, and parts of Scandinavia --- and would make up much of the later highly mobile pre-Roman Celtic tribes that were centered initially between the North Sea, the Seine, the Rhine, and the Danube, as well as the populations that later comprised the main Germanic tribes in Western Europe i.e. the Saxons, Angles, Jutes, Frisians, Franks, Goths and Vandals.


    After the migration into the north country, and about 7, 000 years ago, our Brewer family ancestors were confronted with a new and dramatic change of lifestyle, referred to today as the Neolithic revolution, and they eventually had to choose between continuing the life of their hunter-gatherer fathers, or adapting to newly imported techniques of agriculture and accepting the cultural modifications such a move would entail. After the conclusion of the Upper Paleolithic (or Mesolithic) about 10, 000 years ago, began a period called the Neolithic, which in Europe is strictly associated with the appearance of agriculture. The introduction of farming and animal domestication did more to transform mankind’s way of life than anything before or since.  It created permanent, settled communities -- the beginning of civilization as we now understand it.


    For nearly a thousand years a clear frontier existed, [Note 3] a boundary where to the east and south of the line were farmers and scattered bands of hunter-gatherers and to the west and north were hunter-gatherers, including a good part of our Brewer family Hg I-2b population, who, as they began to experiment with agriculture, also began constructing immense stone megaliths.  Those monuments were large stone dolmens (burial chambers with vertical flat stones capped by flat stones placed horizontally) or menhirs (tall standing stones), and appeared in the regions along the Atlantic coast of Europe from the Iberian Peninsula to Denmark, and along the western coasts of England and Ireland. Stonehenge in England is the most famous example.


    It is quite certain that our Brewer family progenitors encountered and understood the significance of these monuments.  They likely participated in the construction of one or more. These 4,000-5,000 year old megalithic stone graves and structures from the Neolithic lie in a belt, which stretches from east of the Netherlands, over Westphalia, Lower Saxony, Schleswig-Holstein, Mecklenburg-Western Pomerania and Saxonia-Anhalt; exactly where the majority of our Haplogroup I-2b lived, and still live, and so encompassed the area in which our Brewer family ancestor of that period lived, fathered, and raised his family.


    Because agriculture supported higher population densities than the old foraging techniques, populations rapidly increased and by about 3, 000 years ago (1, 000 BC) there were about two persons per square kilometer. Over the territory of the present Netherlands, there must have been about 80, 000 inhabitants.  I am assuming that our Brewer family ancestors settled there and made up part of that population; alternatively, they may have settled in northern Germany and eventually migrated further northward to the Netherlands.  Either way, they were soon to become part of the Celtic culture.  In the first millennium BC, the Netherlands were invaded by Celts, a people who were successful farmers and excellent copper smiths. They were descendants of the Iron Age communities that were named for Hallstatt in western Austria and La Te`ne in Switzerland.


    The Celts were, and still are, a conglomeration of peoples speaking a series of related  languages. They are a linguistic group, not really a national, ethnic, or racial one. The Celts laid great store on language and on the culture which the language conveyed.  The early Celtic heartland, around 2, 800 years ago ( 800 BC) has been determined to be in the region of the upper reaches of the Rhine, the Rhone, and the Danube,  These rivers still retain the Celtic names. [Note 4]  The Celtic influence was spread not only by movement of people but also by the export of culture and language.  In the last centuries of the first millennium BC the Celts acted as middlemen to the expansion of trade between the Mediterranean and the people of the north and west, trading wine, salt, swords and fine jewelry with the growing Roman Empire. The Celtic community reached its peak from 400 BC (2, 400 years ago) to 200 BC. [ Note 5]  Although Celtic was the “Lingua Franca” of the time, the northern German and Netherland tribes, Anglo-Saxon and Franks, retained their germanic language. Our Brewer ancestors likely spoke both a Celtic dialect and early Dutch or German.


    The Low Countries [Note 6] , inhabited by Celts and Germanic peoples, were on the eastern border of Celtic Gaul, the Roman province of Gallia. The land south of the Rhine was brought under Roman rule in 51 BC by Julius Caesar as governor of Gaul. The Frisii and Batavi were within the Empire as part of the province of Germania Inferior from AD 14 but the Saxons to the north of the Rhine remained independent. The Frisians and Saxons were among the Germanic tribes who invaded Britain after the Romans left, many of them settling permanently and establishing new kingdoms.


    A wave of Goths passed through the Netherlands around 400 AD, followed by Huns around 450 AD, and by the Germans around 800 AD.  Both Frisia and Saxony were eventually incorporated into the Frankish Empire and converted to Christianity. As the Empire was weakened by Viking and Magyar raids, Frisia became divided into Hainault, Brabant and Upper Loraine. Like Saxony, they were part of the Kingdom of Germany after the 10th century (900 AD) and remained within the Holy Roman Empire despite French annexation of neighboring Flanders. Local feudal lords, headed by the Count of Holland and the Bishop of Utrecht, were almost independent although they owed allegiance to the Holy Roman Empire. In the late 14th century and early 15th, the Dukes of Burgundy built up a chain of territories which included the 17 separate provinces of the Low Countries, some of the richest lands in Europe and presumed ancestral home of our Brewer family.


    In 1500 AD, the population of the geographic region of the Netherlands counted between 900, 000 and 1, 000, 000 inhabitants. This number increased to 1.85 million people in 1650, and then growth came almost to a standstill. During the 1500’s the Protestant Reformation spread through the Low Countries. There was widespread persecution of the Protestants in an attempt to stop the threat to the Roman Catholic church.  In 1566, 1572 and 1576, the Dutch rebelled against the central government of Philip II in Spain which they feared was destroying their traditional liberties. The seven northern provinces were united as the Northern Provinces by the Union of Utrecht in 1579 and armed opposition continued until 1609, forcing Spain to recognize them as independent and they became the Dutch Republic under the Treaty of Westphalia. The remaining area to the west, now Belgium and Luxembourg, was reconquered by Spain and was known as the Spanish Netherlands.  These events would have occurred during the lifetimes of the father (b~ 1600), grandfather (b ~ 1570) and great grandfather (b~ 1540) of our first documented ancestor, Johannes Brouwer (b ~1632). The great grandfather of Johannes was likely to have been the first of the family to be referred to by the surname Brouwer, acknowledging his occupation as the brewer of ales for his village. They were all likely to have been Protestants, and we know our Johannes was a member of the Protestant Reformed Dutch Church.


17th century Netherlands and our Brouwer surname.

    Around 1632 our first historically documented direct ancestor was born; Johannes Brouwer. He was presumably born in Amsterdam, Netherlands, though it is possible he was born in northern Germany and immigrated first to Amsterdam before later emigrating to America. He emigrated to New Amsterdam (New York), in 1657 under the auspices of the Dutch West India company. He was by trade a Blacksmith, though his surname, Brouwer, indicates that in the past, when family surnames were adopted, perhaps by 1500 AD, his ancestor was by occupation a brewer. As mentioned earlier, the great grandfather of Johannes was likely born around 1540 AD and so may have been the first of our ancestors to use the surname Brouwer. Surnames were first adopted in Europe in northern Italy around 1000 AD and the practice gradually spread northward into the Germanic regions and eventually to all of Europe.  By 1500 AD the use of occupations for family names, such as Brauer (brewer), was more common in German speaking regions than in almost any other culture, and in the Netherlands the Dutch name would be Brouwer (brewer). Both names are pronounced identically, as the English would pronounce “Brow-er”. Brouwen in Dutch is the verb “to brew” as is Brauen in German, and the suffix -”er”, added to the stem indicates “one who brews” . Before 1500, communities were so small that everyone would know who “Johannes” was so it is unlikely that any of our ancestors had any need for a surname to distinguish themselves.  Johannes, pronounced as in English “Yo-hannes” was a Dutch forename taken from the Bible, meaning “John” in English (as in John the Baptist of the New Testament), and the diminutive of Johannes was Jan.  In Dutch, sons were often referred to with  “sz” attached to the diminutive of the father’s forename, so John’s son, would be “Jansz” and when he was grown he would be called Johannes Jansz Brouwer, signifying John, John’s son.  This fact is used by some to conjecture that since our ancestor Johannes Brouwer did not use such a patronymic, that he was possibly not of Dutch origin but German.  Until further data is available as to who the father of Johannes was and where he lived, I will continue to assume that Johannes was Dutch, born in Amsterdam, where we know he was married to Jannetje Jans and where their daughter, Jannetje Jansz, was born before the family emigrated to America.

    We have now reached the age of historic record of our ancestor, having traversed some 15, 000 years and between 600 and 750  generations of our family.



[1] The Magdalenian, refers to one of the later cultures of the Upper Palaeolithic in western Europe. It is named after the site of La Madelaine in the Dordogne region of France. Originally termed the age of the reindeer the Magdalenian is synonymous with reindeer hunters although Magdalenian sites also contain extensive evidence for the hunting of red deer, horse and other large mammals present in Europe towards the end of the last ice age. The culture spans the period between c. 18,000 and 10,000 BP (Before the Present), towards the end of the last ice age. The later phases of the Magdalenian are also synonymous with the human resettlement of northwestern Europe after the Last Glacial Maximum.  The Magdalenians are  known for their elaborate worked bone, antler and ivory which served both functional and aesthetic purposes. Cave sites such as the Lascaux contain the best known examples of Magdalenian cave art. The earliest Magdalenian sites are all found in France.

[2]   pages 15-16 “Paleolithic Indo-Europeans” , on line Aug-Dec 2004  at:www.enter.net/~torve/trogholm/wonder/indoeuropean/indoeuropean1.html

[3]  page 169 “Mapping Human History” Steve Olsen, Mariner Books 2003

[4]  page 53 ‘The Isles - a History” Norman Davies, Oxford Univ. Press 1999

[5[ page 259-260 “The History and Geography of Human Genes” L. Luca Cavalli Sforza Princeton University Press 1994:  The Celtic tribes along the Danube and Rhine (to the North Sea -- primary area of Hg I-1c).  Hallstatt and La Tene 3,000 years ago (1,000 BC forward ) and migrations.  Celtic community was at its peak after 400 BC - 2,400 years ago.

[6] The Low Countries: Comprising the lands around the Rhine delta and extending north to the Frisian coast, these regions have had  an influence on European and world history all out of proportion to their size, owing to their strategic location and the patient enterprise of the inhabitants. East (German) Frisia and West (Dutch) Frisia are coastal regions in the northern Netherlands, extending into Germany as far as the mouth of the Weser. The Frisian people have lived on these sandy strands for ages, and are notable to speakers of English as having the language most closely related to English. This is unsurprising, as these are the shores from which the Anglo-Saxons embarked upon their conquest of Britain.