(2013) ORPA Distribution and Diversity

By Hans De Beule

Based on current I-L38 frequencies and diversity, this page pinpoints the hypothetical location of origin of the Most Recent Common Ancestor (MRCA) of most present-day I-L38s 5,000 years ago).

Y-DNA diversity and frequency and are two important indicators in the search of the point of origin of a Y-DNA haplogroup. The more diverse and frequent a haplogroup is in a region, the deeper its root in that region. Using the Oldest Reported Paternal Ancestor (or ORPA) coordinates of I-L38 samples their distribution and frequency is mapped. The goal of this approach is to determine the most likely region of origin/expansion of haplogroup I-L38.

ORPA Distribution

Generally speaking, a substantial series of genealogical documents are present in Western-European history ever since the beginning of the seventeenth century. The Council of Trent, closed in 1563, had required the registration of baptisms and weddings; yet as a result of wars from the sixteenth through to the twentieth century, the oldest parish registrations were mostly lost. (van Uytven et al., 2011)

Therefore, most of the Western-European genealogists have a reliable Oldest Reported Paternal Ancestor (ORPA) born between 1600 and 1750. (Rasmuson, 2008; Larmuseau et al., 2012)

Out of a collection of 496 I-L38 samples from public databases, 130 unique family names could be tied to a fairly reliable ORPA location. For 108 of them also the ORPA year of birth is known (see the table below).

Eighty percent of the ORPA years of birth can be dated between the beginnings of 15th and the end of the 19th century. The average birth year of these samples is 1738.

Distribution of 130 I-L38 ORPA locations with average birth year 1738. The Rhine is highlighted as a geographical point of reference (I Lower Rhine, II Middle Rhine, III Upper Rhine, IV High Rhine). The letters in the red balloons indicate the DYS385a,b values, used to measure the genetic diversity of the I-L38 ORPAs.

ORPA Diversity

To investigate the diversity of I-L38 in relation to its geographical spread a simple indicator was sought. For pragmatic reasons the choice fell upon the multi copy marker DYS385a,b:

Almost all samples have known DYS385a,b values.

DYS385a,b enables us to divide I-L38 into 16 DYS385 clusters only using one (multi copy) STR locus. Standard testing does not reveal the order of DYS 385a and 385b. By convention the lowest value is reported first, a Kittler test however can reveal the true order of these alleles. Kittler tests showed that it is safe to generalize that all I-L38 samples have the same High-Low order.

The mutation rate of both copies of the multi-copy locus DYS385a,b is 0.00226. (Chandler, 2006) This means that on average every 221 generations (5500 to 6500 years) one of the copies mutates. Since the MCRA of most I-L38’s lived around 4000 years ago only few DYS385 mutations will have accumulated.

Thus, the multi-copy marker DYS385a,b offers a way to divide I-L38 into a practical number of clusters. Among the 130 I-L38 samples, the following 16 DYS385 a,b combinations were found:

Allocation of 130 I-L38 samples into 16 DYS385a,b clusters

The following figures show Google Earth maps that display the frequency and DYS385 diversity of 130

I-L38 ORPA locations with average birth year 1738. The letters in the balloons indicate the DYS385a,b values, used to measure the genetic diversity. Using a grid, these maps are divided into squares of 323 x 323 kilometer or (201 x 201 mile). The figures next to the balloons indicate:

• the number of I-L38 samples into the geographical square (indicating the frequency);

• the number of DYS385 combinations into the geographical square (indicating the genetic diversity).

I-L38 ORPA frequency and diversity in Scotland and Scandinavia

I-L38 ORPA frequency and diversity in Ireland and England

I-L38 ORPA frequency and diversity in the Low Countries (Belgium and the Netherlands)

I-L38 frequency and diversity in the Alpine region – the red arrow indicates the regions with highest frequency and DYS385 diversity (=5,4)

Discussion: Exploring the Possible Relation Between I-L38, Alemand and Franks

The three regions with the highest frequency and diversity scores are:

• Frequency: 5 - diversity: 4:

• Heidelberg region, Germany,

• Flanders, Belgium though his result may be biased because proportionally much data were included from the Hertogdom Brabant study.

• Frequency: 4 - diversity: 3:

• Norfolk region, England. One of the samples is named “Holland” suggesting a relation with the Netherlands

• Frequency: 3 - diversity: 3:

• North of Switzerland – this is the German speaking part of the country

• Northhampton & Southampton.

The highest I-L38 frequency and diversity score is found in the Heidelberg region:

The Heidelberg region has the highest I-L38 frequency and diversity. Note the central position of the river Rhine and the town in the north called Frankenthal (literally valley of the Franks)

Historically the Heidelberg region was known as the Roman Province Germania Superior; a region protected by “limes” (border defences) to stop the infiltration of Germanic people from the other side of the Rhine. From 230 AD on the Alemans broke through the limes and infiltrated the area.

The Alemans (literally “All men”) were a confederation of Germanic tribes located at the Upper Rhine river. In the late 3rd century Crocus (or Chrocus) became king of the Alemans. In 260 AD, under his command the Alemans captured the Roman Province Germania Superior, and expanded into present-day Alsace and northern Switzerland; establishing the German language in those regions.

The Aleman connection also might be a partly explanation of the presence of haplogroup I-L38 on the British Isles. Historic sources also mention Alemans who crossed the channel:

• 276 - 279 Probus overcame a Alemanic rebellion around the Rhine and sent the Alemans with their leader Igillus to Brittania, where they settled and where they helped the emperor whenever a rebellion broke out. (Zosiumus)

• 306, Crocus, was described as "Alamannorum rege" and supported the Roman emperor Constantius Chlorus who fought the Scots and Picts. After the death of emperor Constantius Chlorus in Eboracum (York), Crocus played a key role in the acceptance of the son of Chlorus as new emperor- undoubtedly supported by his Alemanic troops. (Aurelius Victor)

• 372 Valentinian sent the Alemanic Fraomarius of the Bucinobantes, together with other Alemanic troops under command of Bitheridius and Hortarius, to Britannia. (Ammianus Marcellinus)

Looking at the demography of the Heidelberg region (in casu: the Rhineland) it is remarkable that demography increased in Roman times but fell back dramatically in Merovingian time.

Figure 15: demography in the Rhineland

In 496, the Alemans were conquered by the Franks, a competing Germanic people. Subsequently the region was ruled by the Franks and became part of the Merovingian and subsequent Carolingian Empire in the following centuries.

Written sources, archeological artifacts and linguistics show that the influence of the Franks expanded from the Rhine to the North Sea:

• One panegyric for the Emperor Constantius Chlorus, explicitly mentions Franks, in the area of the river Scheldt in Flanders, Belgium during the late 3rd century AD. (in 't Ven I.& De Clercq W. 2005)

• The finds of Germanic pottery in Zele, Flanders, Belgium confirms this statement and indicates the presence of Germanic settlers during the second half of the 3rd and the early 4th century. (in 't Ven I.& De Clercq W. 2005)

• The toponym “Zele” refers to the Old Germanic word “sali” meaning “saloon” in its original meaning: a large hall. Recent research showed that such a distinguished Frankish large hall, in the early middle ages, was the center of a larger (Frankish) settlement. (Debrabandere, 2010)

Last update: November 2013 - Hans De Beule