Table 1.

The British pig breeds

	Breed	Sample size	Type	Status1	Sampling4
1	Berkshire	73	Traditional	At Risk	PigBioDiv [15] and USA
2	British Saddleback	30	Traditional	Minority	PigBioDiv [15]
3	Duroc	31	Commercial		2 European and 2 USA populations [16]
4	Gloucestershire Old Spots	24	Traditional	Minority	PigBioDiv [15]
5	Hampshire	30	Commercial		PigBioDiv [15]
6	Landrace	30	Commercial		3 European and 2 USA populations [16]
7	Large Black	30	Traditional	Vulnerable	PigBioDiv [15]
8	Large White	34	Commercial		3 European and 2 USA populations [16]
9	Mangalica	26	European2		PigBioDiv [15]
10	Meishan	24	Asian3		PigBioDiv [15]
11	Middle White	30	Traditional	Vulnerable	PigBioDiv [15]
12	Pietrain	21	Commercial		2 European and 1 USA populations [16]
13	Tamworth	30	Traditional	At Risk	PigBioDiv [15]
14	Welsh	33	Traditional	At Risk	This study
		446

¹ population status quantified by the number of breeding females: Vulnerable = 300; At Risk = 500; Minority = 1000; taken from Rare Breeds Survival Trust ( http://www.rbst.org.uk/watch-list/pigs), ² first imported to Britain from Hungary in 2006, ³ first imported to Britain from China in 1800s, ⁴ the sampling protocol is further described in the materials and methods.