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mark of Jan Broersen Decker

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(Reprinted with permission, see below)

by Wayne R. Decker, Ph.D.*

Jan Broersen Decker settled in the Dutch colony of New Netherland in the mid-1600s and has many descendants. There is uncertainty, however, concerning some of his children. Was Cornelius Janse Decker, for whom no birth record exists, a son or a stepson? Also, no birth record exists for another son, Jacob Janse Decker. A recent DNA study using a leading genetics laboratory has resolved these paternity questions.

Jan Broersen was in Esopus (later named Kingston) in 1658, when his mark was among the nine signers to the agreement to move into a stockade for protection. Jan Broersen also affixed his mark to the petition requesting that Domine Blom be brought to be the first minister of the Old Dutch Church of Kingston. Jan’s civic activity is further attested to by his military service in the militia and his appointment as a town magistrate.[[1]]

Of Jan Broersen’s eight children listed in some genealogies, only four children are found in primary records.[[2]] In the baptismal records of the Old Dutch Church of Kingston, Jan Broersen and Heyltje Jacobs are listed as parents of the following children:[[3]]

Gaerleff (Gerrit), bap. 26 February 1662

Grietje (Margaret), bap. 31 August 1664

Maddelen, bap. 3 October 1666

Fietie, bap. 18 June 1671

It has been suggested that Cornelius came into the family as a stepson at the time of Jan Broersen Decker’s second marriage in 1679 (the first instance of Jan Broersen using the surname Decker).[[4]] Jan’s second wife, Willemtje Jacobs, was a younger sister of Jan’s deceased wife, Heyltje Jacobs, and had been married twice before. Willemtje was married second in 1668 to Jan Cornelisse, who died in 1669.[[5]]

A chief proponent of the stepson theory was Alfred Decker Keator, at one time Director of the Pennsylvania State Library in Harrisburg, who wrote:

. . . there is no proof that Jan Broersen was the father of Cornelius Jansen Decker of Kingston and Shawangunk. The earlier “Deckerologists” were divided in their opinions on this, and it was I who brought up to date that Cornelius “might” be the son of Jan Broerse. Two or three years ago, I had a flash of inductive reasoning when I was studying the relationships of Jan Broerse, van Husum, Denmark, and his “hired man,” I suppose, Jan Cornelisse, van Gothenberg, Sweden. These men were both carpenters and associated in the building business in Wiltwick, later Kingston, N.Y. . . . Now here’s my present theory. There is no baptismal record of Cornelius Jansen Decker, but he m. Elsie Ten Broeck in 1695. The record states he was b. in Kingston (Wiltwick) and from Jan Cornelisse’s marriage date, May 1668, to his death in 1669 would no doubt encompass Cornelius Janse’s birth date. He was a boy say 9 or 10 years old when Jan Broerse married his mother, and what’s more natural than being adopted by his former uncle Jan Broerse and taking his surname? There is lots of supporting circumstantial evidence to corroborate this and no direct evidence to disprove it. . . . The period I just indicated, 1668 to 1669, was one when the famous old church in Kingston had no regular minister. The pulpit was supplied by Albany and New York ministers who performed some baptisms no doubt but filed them with their home church record. Alas, the Albany church records of that period have been totally lost or destroyed.[[6]]

Thus Keator sets up the hypothesis, but he doesn’t give the “supporting circumstantial evidence.” Benton Weaver Decker reports without supplying sources:

It is said that son Cornelius Janse Decker was the son of Willemtje by a previous marriage and as was customary was adopted by Jan Broerse. Also, it is said by others that Cornelius was the twin of Gerret [b.] 1662. There is no known record to support either of these two conclusions.[[7]]

As she begins listing the descendants of Cornelius Janse in her “Lineage of the Decker Family,” Mrs. G. B. Munger admits ignorance:

I do not know the father of Cornelius Decker with which the following begins, but his marriage record in Kingston Church Records states that he was born in Kingston. Therefore I have marked him second generation. From the constant recurrence of the name John I infer that his father’s name was John, presumably John Brouerson Decker.[[8]]

Evidence of the close family relationship between Jacob, Gerrit, and Cornelius Decker is found in a land grant in Shawangunk in southern Ulster County.[[9]] On 13 September 1694, William and Mary, King and Queen of England, granted the land patent to “John Van Camp, Jacob Brewerson (sic) Senjor, Jacob Brewerson Juniour, Cornelius Brewerson, John Evertson, and William Johnson, all of our County of Ulster Yeomen.” The following interesting explanation has been provided by historian/author Marc B. Fried:

. . . The use of Jacob Senior and Cornelius of their father’s Patronymic, as a surname, seems to have been a somewhat temporary expedient; this family soon adopted the surname Decker. Shawangunk patentees Jacob Senior and Cornelius were thus members of the first native born generation of the Ulster County Decker family. Patentee Jacob Brewersen Junior was the son of Gerret (Gaerleff) Decker and grandson of Jan Broersen. Jacob Junior was thus not a son, but a nephew, of patentee Jacob Senior. He was only about 10 years old at the time of the Patent. Apparently Gerret was a partner with his brothers in this land purchase, but wished his son Jacob to be the patentee of record.[[10]]

Additional support for the relationship is found in Worden’s transcript of the Shawangunk church records, in a memorandum added at the close of the 1751-1784 marriage records, which states:

1679 Dec.14 Jan Broersen DECKER, widr, to Willemtje Jacobs of Marbletown. First wife was Heyltje Jacobs. He was ancestor to the Shawangunk Deckers.[[11]]

Evidence that Cornelius was the son of Jan Broersen Decker and his wife Heyltje Jacobs is also found in the Dutch naming tradition. Cornelius Decker and his wife Elsie Ten Broeck named their second daughter Heyltje, indicating that Cornelius’ mother was Heyltje not Willemtje.[[12]]

Primary records prove only Gerrit Janse Decker to be a son of Jan Broersen Decker and Heyltje Jacobs. The opportunity to obtain direct evidence proving identical paternity for undocumented sons inspired this Y-chromosome DNA study. Descendants of Cornelius Janse Decker, Jacob Janse Decker and Gerrit Janse Decker, second generation Deckers from Ulster County, were chosen for this study. Relative Genetics[[13]] analyzed buccal swabs from five documented 10th and 11th generation direct-line male descendants of these second generation ancestors (the five are identified here only by ID numbers). The first four generations of drop line charts from each second generation ancestor to the participants are presented here. The paternal lines of the participants include, from Cornelius Janse Decker:[[14]]



      2.  Cornelius Janse Decker (b. abt. 1670, d. 4 Mar. 1702)

           m. Elsie Ten Broeck (b. 1676, m. 22 Dec. 1695, d. 9 June 1725)

           3.  Johannes Decker (b. 16 May 1696, d. 23 Jan. 1742)

                m. Marytje Matthyssen Jansen/Van Keulen (bap. 13 Sept. 1704, m. 17 May 1726)

                4. Cornelius Decker (b. 6 Jan. 1731, d. 4 Aug. 1812)

                    m. Elizabeth Decker (b. 11 Nov. 1740, m. 14 July 1766, d. 10 June 1813)

                    5.   Johannes Cornelius Decker (b. 2 June 1767, d. 4 Apr. 1812)

                          m. Sarah DePuy (b. 9 June 1770, m. 15 Nov. 1787, d. 30 Sept. 1818)

from Jacob Janse Decker:[[15]]

      2.  Jacob Janse Decker (b. abt. 1656, d. aft. 29 May 1720)

           m. Belytje Jans Bastiaanesse (b. 1659, m. 8 Dec. 1678)

           3.  Jan Decker (bap. 28 Sept. 1679)

                m. Thyssje Bogart (m. abt. 1706)

                4. Cornelis Decker (b. 1721)

                    m. Jannetjen Konyn (b. 17 Apr. 1726, m. 1745)

                    5.   Jacob Cornellis Decker (b. 8 Aug. 1756, d. 16 June 1838)

                          m. Asenath Barden (b. 5 June 1764, m. 12 Dec. 1780, d. 6 July 1850)

                4. Gerrit Decker (b. abt. 1731)

                    m. Jannetje M’Clean

                    5.   Myndert Decker (bap. 28 Mar. 1762)

                          m. Saartje or Sarah Schuts (m. 8 May 1701)

and from Gerrit Janse Decker:[[16]]

      2.  Gerrit or Gaerleff Decker (bap. 26 Feb. 1662, d. bef. 1696)

           m. Magdalena Willemsen Schut (b. abt. 1667, m. 2 Apr. 1684)

           3.  Jacob Gerritse Decker (bap. 24 Feb. 1684, d. 3 May 1761)

                m. Geertje Van Wagenen (b. 1 Sept. 1686, m. 17 Sept. 1709, d. 13 Apr. 1776)

                4. Gerrit Decker (b. 2 Oct. 1711, d. 1 May 1786)

                    m. Catharina Schut (bap. 13 May 1716, m. 6 Oct. 1733, d. 11 Apr. 1770)

                    5.   Petrus Decker (b. 3 Feb. 1759, d. 28 July 1840)

                          m. Annatje Decker (b. 25 June 1761, m. 10 Aug. 1782, d. 16 Feb. 1833)

                4. Jacob Decker (b. 3 Oct. 1715)

                    m. Eva Buchstaber (b. 1728, m. 1747)

                    5.   Phillippus Decker (b. 11 Aug. 1747)

                          m. Elizabeth Wallace

Relative Genetics examined 26 sites, which are sections of the very long strand of DNA that makes up the Y-chromosome.[[17]] These sites are considered to only occupy space on the chromosome and do not play a part in determining physical traits. At each identified site, called a locus, the number of Short Tandem Repeats (STRs), repeating units of DNA, are counted. The collection of loci and the associated number of STRs at each locus defines the haplotype of the male (see table). The only way for a son to have a different haplotype from his father is due to mutation. The rate of mutations is small and statistically predictable. Of course, adoption, illegitimacy, or infidelity of the mother would frustrate the line of paternity.

In this study, for the descendant of Cornelius Janse, both descendants of Jacob Janse, and one descendant of Gerrit Janse, the number of STRs match at each of the 26 loci, indicating a common male ancestor.[[18]] For the other descendant of Gerrit Janse the number of STRs match at 25 of 26 loci with the locus DYS385b having 15 rather than 14 STRs. This is consistent with a single mutation somewhere in the 300-plus years to Gerrit’s son Jacob Decker (1684), and statistics indicate that Gerrit is the male ancestor of both men with 95% confidence. Thus, these five partici­pants have a common male ancestor, who must be Jan Broersen Decker.[[19]]

The haplotype of Jan Broersen Decker that has been deduced from five direct line male descendants of three of his sons is:[[20]]

Locus STRs Locus STRs Locus STRs
DYS385a 11 DYS394 14 DYS461 11
DYS385b 14 DYS426 12 DYS462 11
DYS388 12 DYS437 15 GGAAT1B07 10
DYS389 14 DYS438 12 YCAIIa 19
DYS389II 30 DYS439 12 YCAIIb 22
DYS390 24 DYS447 25 Y-GATA-A10 14
DYS391 10 DYS454 10 Y-GATA-C4 23
DYS392 13 DYS455 10 Y-GATA-H4 12
DYS393 13 DYS460 11    

Jan Broersen haplotype. The haplotype analysis provided by Relative Genetics consists of 26 loci on the y-chromosome and the associated number of repeating units of DNA.

It should be noted that the study would have resulted in uncertainty in the haplotype of Jan Broersen Decker if only the descendants of the baptism-documented-son Gerrit had been used. The two Gerrit descen­dants differed by one STR at locus DYS385b, which was assumed to have been caused by a mutation.  The uncertainty was resolved when DNA from the two descendants of Jacob and the descendant of Cornelius unanimously agreed with one Gerrit descendant and thus showed that the line of the other descendant of Gerrit had the y-chromosome mutation.

In conclusion, the DNA study reported here has provided evidence that Jan Broersen Decker van Husum was father of Jacob Decker and Cornelius Decker in addition to Gerrit Decker, who was known to be a son from Kingston baptismal records. Therefore, Cornelius Decker was not a son of Jan Cornelisse, van Gothenberg, Sweden, which was suggested by Keator.

* Copyright © 2004, The New York Genealogical and Biographical Society. Dr. Decker’s address is 2394 E. 6150 S, Ogden, UT 84403. Thanks for encouragement as well as historical and technical aspects of this presentation to Bonnie Decker Tippets, John Shields Decker, Mark T. Decker, and Diahan Southard. Thanks to Anita Lustenberger, C.G., for helpful suggestions in review.


[1] Mrs. G. B. Munger, “Lineage of the Decker Family,” Olde Ulster, 2(1902):244. Holdridge Ozro Collins, “The Westfall Family,” Record 33(1902):88.
[2] Listed as “probable children,” Broer Jansen Decker, Jacob Jansen Decker, Gerrit Jansen Decker, Grietje Janse Decker, Maddelen Janse Decker, Cornelius Jansen Decker, Titje Janse Decker, and Fietje Janse Decker, in Lewis D. Cook, “Jeurian Teunissen Tappen and His Descendants, Appendix A. The Decker Family of Kingston, New York,” Record 97(1966):215-17. Another list of Jan Broersen Decker’s children, Jacob Jans, Broer, Gaerleff Janse, Grietje, Madelen, Cornelius Janse, Fietje, and by the second marriage Jurien Jans, is given by Benton Weaver Decker, The Decker Genealogy, Some Early Descendents of the Dutch Immigrants, Johannes Gerretsen (Decker) and Jan Broersen (Decker) (Budget Book Manufacturing Co., 1980), pp. 129-30.
[3] Baptismal record nos. 16, 43, 72, and 112 in Roswell Randall Hoes, Baptismal and Marriage Registers of the Old Dutch Church of Kingston, Ulster County, New York, 1660-1209 (New York, 1891), pp. 2, 4-5, 8.
[4] Marriage no. 45 in Hoes, Baptismal and Marriage Registers, 505.
[5] Marriage no. 25 in Hoes, Baptismal and Marriage Registers, 502.
[6] Letter from Alfred Decker Keator to Lorenzo B. Decker, dated 25 Apr. 1965.
[7] Decker, The Decker Genealogy, 129.
[8] Munger, “Lineage of the Decker Family,” Olde Ulster, 5:155.
[9]  New York State Patents 6:464-67, N.Y. State Archives, Albany, also Family History Library, Salt Lake City, microfilm 0945289.
[10]  Marc B. Fried, Explanatory Text of the 1694 VanCamp/Decker Patent, September 28, 1983. The text is on public display accompanying the collection of framed photographs of documents relating to the early history of Shawangunk at the Shawangunk Town Hall, Wallkill, N.Y.
[11]  Jean D. Worden, Reformed Protestant Dutch Church of Shawangunk, Ulster County, New York (Franklin, Ohio, 1986), p. 227 (italics added). It is not clear when or by whom the memorandum was written.
[12]  Munger, “Lineage of the Decker Family,” Olde Ulster, 5:155.
[13]  Relative Genetics, 2495 South West Temple, Salt Lake City, UT 84115, telephone 801-461-9760, fax 801-461-9761, www.relativegenetics.com.
[14]  Munger, “Lineage of the Decker Family,” Olde Ulster, 5:155-59, 181. M. I. Young, “The Decker Family Bible Record,” Record 27(1896):131-32. Family records of ID 1546A.
[15]  Family records of participants identified as ID 1536C and ID 5178.
[16]  Munger, “Lineage of the Decker Family,” Olde Ulster, 2(1906):245-48. Family records of participants identified as ID 2481 and ID 2584. International Genealogical Index (IGI), Family History Library, Salt Lake City.
[17]  Decker Family Study (Revised), Relative Genetics, 25 Nov. 2002, p. 4.
[18]  Ibid., 25 Nov. 2002, pp. 1, 4. Supplemental report, Relative Genetics, T005178, no date.
[19]  DNA evidence shows—supporting historical associations, patronymics, and naming traditions—that Jacob and Cornelius share a common male ancestor with Gerrit, who is documented in baptismal records as a son of Jan Broersen Decker. Jacob and Cornelius both appear on record with the patronymic Jansen, indicating their father was named Jan, and no Jan Decker other than Jan Broersen has been found in New Netherland. Jacob, Cornelius, and Gerrit’s son all appear on the 1694 patent as Brewerson, i.e., Broersen. Therefore, Jan Broersen Decker must be the father of Jacob and Cornelius.
[20]  Decker Family Study (Revised), Relative Genetics, 25 Nov. 2002, p. 4.

Reproduced with the permission of The New York Genealogical and Biographical Society and the author.

The article, "Using DNA to Establish the Paternity of Two Undocumented Sons of Jan Broersen Decker of Kingston," by Wayne R. Decker, was originally published in The New York Genealogical and Biographical Record, volume 135, number 1 (January 2004), pages 3-8.


March 31, 2004