R1b is the most common haplogroup in Western Europe with especially high incidence in Spain, Portugal, Western France and Ireland. The modal, (or most commonly occurring haplotype), for this R1b of Western Europe is called the Atlantic Modal Haplotype, (AMH), Ysearch ID, C7BED. For more information on AMH see the Links page.
The first 25 markers of AMH in Ysearch format are:-
AMH - DYS Marker Values
393
390
19
391
385a
385b
426
388
439
389_1
392
389_2
458
13
24
14
11
11
14
12
12
12
13
13
29
17
459a
459b
455
454
447
437
448
449
464a
464b
464c
464d
9
10
11
11
25
15
19
29
15
15
17
17

Because of the large number of males that fall within this haplogroup, efforts have been made to find clusters that show differences in the Short Tandem Repeat,(STR), of their alleles from the AMH by looking for similar variations in the haplotypes. Henwood is only one allele different from the first 12 alleles on the Atlantic model.

Reference: http://www.irishtype3dna.org/

The Henwood and the Robinson line in our family are both in dna language listed as R1b1b2 haplogroups. In finding information about the dna of Henwood, the paragraph below is important. I didn't know it could be called ht15. The R1b1b2 of my mother's father (Robinson) is different by being much older than this line and coming from the East. I find this out by the number on DYS on the Robinson line being 12. The Henwood's DYS 393 is 13.

The main European groups consisting of R1b1b2 (ht15) which the Henwood line is included are probably less than 6 thousand years old although some still argue for a pre Ice Age existence.