Although genetic genealogy has three main approaches, namely Y-DNA, mitochondrial DNA, and autosomal DNA analysis, the optimum method for a surname project is Y-DNA analysis. The Y chromosome is passed essentially unaltered from father to son, unlike other chromosomes that comprise a combination of paternal and maternal DNA.(Aside: although a male only receives an X chromosome from his mother, this X chromosome contains a combination of DNA from the X chromosomes of both of his maternal grandparents). Therefore all male Brays descending from the same Bray patriarch should have near-identical Y-DNA results. Rare and random variations do occur, and comparison of such variations can assist in determining the likely degree of the relationship between two matching individuals.

Surname authorities describe the British surname Bray as toponymic (i.e.derived from a place name). The Oxford Dictionary of Surnames gives it as “Bray, English: habitation name from places in Berks and Devon. The former is probably so called from OF (old French) bray marsh, the latter from the Cornish element bre hill.” This implies that the families that took the name Bray lived in or near or came from a place already called Bray (spelling variable). In Britain, people gradually began to adopt hereditary surnames from about 900 years ago and by about 700 years ago, they were stable and everyone had one. Well within the reach of the Y-DNA test.

The Bray surname has historically been adopted independently by several unrelated families. That this project contains Brays who descend from a variety of unrelated Bray patriarchs should therefore come as no surprise. When two Brays have matching Y-DNA results we know that they share a common ancestor along a pure paternal line, who was almost certainly also surnamed Bray. Sometimes there will be a trail of documentary evidence tracing back to this common ancestor, but often the common ancestor will have lived too long ago for a complete paper trail to exist. When a complete paper trail does not exist, comparison of Bray pedigrees of the matching individuals can provide information that, without genetic genealogy, could not otherwise be obtained. To illustrate this point: if, for example, a member of a Bray family that can be traced back no earlier than to the arrival of a Bray patriarch in America matches a Bray from Britain whose Bray ancestors can be traced sufficiently far back in time to a particular location in Britain, the likelihood is that this particular location is also the previously unknown (or, more precisely, long forgotten) location of origin of the Bray family that settled in America.

It is likely that many Bray families have British origins, but the Bray surname also appears as native to Ireland and France. A look at surname distribution maps for the Bray name in Britain during the mid 1800s shows the concentration of the name in Cornwall and Devon with much smaller numbers in other southern counties together with a number in Yorkshire centred on Huddersfield. A study of Cornish baptismal records from the beginning of registers up to 1800 show a large number of Brays in the parish of Gwennap and surrounding towns of Camborne and Redruth, some 36% of all Brays in Cornwall, and thus we can say with confidence that this area is one of the sources for our name. There is a large hill called Carn Brea beside Camborne and there are small hamlets called Carn Brea Village, Brea and Higher Brea beside this hill. This was known as the richest copper and tin mining area in Cornwall stretching back to ancient times. The Gwennap church is quite large and dates back to the 12th century which is around the time family names were being adopted. 

The English census taken every 10 years from 1841 shows 1685 Brays in Cornwall and 820 in Yorkshire, however the Bray population in Cornwall did not grow over the years and in fact slowly declined possibly due to migration as mines closed, yet the population in Yorkshire continued to grow. By the 1891 census, Yorkshire had become the dominant place of origin as the numbers were reversed, the number of Brays in Yorkshire was 1543 (again centred in Huddersfield and surrounding districts) and there were 1308 in Cornwall, in 1911 the numbers had become Yorkshire 1843 and Cornwall 1385. See Group F for the Yorkshire Brays.

It has been suggested that some Irish Brays may have derived their surname from the O Breaghdha family of Munster who appeared in the writings of Giolla na Naomh O'Heerin (an Irish historian and bard who died in 1420).According to 'Annals of the Four Masters' (1442) O'Heerin also wrote that O'Broith, or O'Bree, was chief of the Magh Seadna. Contemporary historian Michael C. O'Laughlin ('The Book of Irish Families Great and Small') equates the surnames O'Bree and O Breaghdha with Bray.

Bray as a native French surname can be found frequently on the Normandy/Picardy border in Pays de Bray. The Bray surname is also found historically in Saone-et-Loire in central France. It is known from sources such as the “Roll of Battle Abbey” that men from the region of Bray were part of the Norman invasion in 1066 and that settlers from these regions would have moved to Britain during the period of the Norman Conquest which followed. One Bray family represented in this project traces to the surname Bret in Isere, in the Rhone-Alpes region of France, but the surname evolved to Bray when the family emigrated to Canada shortly before 1717.

The Bray surname DNA project currently contains samples from several groups of Brays with diverse origins.

The Bray surname featured in Y-DNA research by geneticists Dr Turi E. King and Professor Mark A. Jobling, of the University of Leicester, entitled “Founders, Drift,and Infidelity: The Relationship between Y Chromosome Diversity and Patrilineal Surnames” , which was published in 2009 in Molecular Biology and Evolution (Mol Biol Evol. 2009 May; 26(5): 1093–1102). Although Dr King’s principal area of research is Y-DNA, she is best known for her analysis of mitochondrial DNA from the exhumed body identified by University of Leicester as that of King Richard III. Professor Jobling’s principal area of research is Y-DNA. They analysed 1678 Y-DNA samples within 40 British surnames; the latter were chosen to represent a wide range of surname type and frequency. They concluded that sharing a surname significantly elevates the probability of sharing a Y-chromosomal haplogroup, and that rarer surnames show higher degrees of shared ancestry. The study also included a control group of 110 men who all had different surnames from each other and from the 40 surname-specific groups. The total number of bearers of the Bray surname (including surname variants) in the 1996 UK electoral register was documented as 12195, making Bray the third most common surname (after Smith and King) of the 40 surnames studied in this research. 29 of the 1678 Y-DNA surname-specific samples were collected from male Brays, with fewer samples from Brays than from most of the other surnames studied. Of the 29 Bray samples, 52% were haplogroup R1b1, 28% were haplogroup I, 3% were haplogroup R1a, 3% were haplogroup R1*, 3% were haplogroup J2, and, unusually, 10% were haplogroup E1a. Haplogroup E1a is very rare, and none of the other surname-specific or control samples belonged to this haplogroup. Despite this, the authors stated that those surnames that did not differ from the controls in terms of haplogroup diversity included the four commonest surnames studied (Smith, King, Bray, and Stead), suggesting that common surnames may contain greater haplogroup diversity than rarer ones. However, when it came to analysing Y-STR haplotype diversity (using 17 selected Y-STR markers), while the Smith group did not differ from the controls, most other surnames were very different from controls, typically showing one or more haplotypes that were shared by many individuals of that surname. This was presumed to be explained by descent from a common ancestor with that surname, although clustering appears to have been very limited among the Brays studied. The Y-STR results for all samples are viewable as supplementary material. So how does this research influence our Bray surname DNA project? The samples were taken from Brays resident in Britain, but, as Bray is not a uniquely British surname, non-British Brays (for it seems clear that the Bray surname has also developed de novo as a surname native to both Ireland and France) may be under-represented, or indeed unrepresented, in this study of King &Jobling.  The knowledge that King & Jobling obtained samples from Brays of haplogroups R1b1, I, R1a, R1*, J2, and E1a informs us that the Bray surname is still suboptimally represented in our project. However, in contrast to the Brays recruited by King & Jobling, the Brays in our project appear to show a stronger tendency to cluster.