1. Charlotte Kelham
Supervisor: Professor Michael Bruford

2. Ancient fine wool breed
White versus coloured fleece
Genetic test essential for
breed survival
White Fleece Coloured Fleece
(Ryeland Flock Book Society, 2012)

3. Underlying genetic basis for coat colour
variation in Ryeland sheep
1. Analysis of the flock book
2. Candidate gene approach
(Deng et al., 2009; Gratten et al., 2010; Norris and Whan, 2008)

4. Five main lines were identified in the
Ryeland flock book:
Pembroke
Ashford Sam
Broomwell Uther
Australian
New Zealand

5. MC1R and TYRP1 seem unrelated to coat
colour phenotype
Dominant white phenotype: A tandem
duplication of a 190-kb segment of the
ASIP gene
Recessive coloured phenotype: A single
copy of the ASIP gene with a silenced
ASIP promoter

6. (Adapted from Norris and Whan, 2008)

7. Proportion of Junction Points
=
Area242/(Area242 + Area238)
Heterozygous White Ryeland
238bp 242bp
Homozygous White Ryeland
238bp 242bp
Coloured Ryeland
238bp

9. Larger sample size
More repeats including a blind trial
Further associations between the
genotype and coat colour phenotype of the
Ryeland

10. White sheep of higher economic value
Increased frequency of coloured sheep
ASIP gene responsible
Genetic test developed