Analysis of stripe patterns in the corneal epithelium. A. Qualitative classification of stripe patterns at different ages. Eyes were classed as having a clockwise (n = 61) or anticlockwise whorl (n = 53), a midline (n = 21) or no clear pattern (n = 51). There was no change in the proportions of clockwise and anticlockwise patterns with age (χ2 test; P > 0.05). B: Comparison of observed and expected frequencies of whorl phenotypes (a-i) in left and right eyes of 56 mice. Animals with unclear patterns in either eye were excluded. There was no significant difference between observed and expected frequencies (χ2 test; P > 0.05) implying that there was no association between the phenotypes of the left and right eyes. Phenotype combinations: (a), clockwise (CW) left (L) plus CW right (R); (b), CW-L plus anticlockwise (ACW) R; (c), CW-L plus midline (ML) R; (d), ACW-L plus CW-R; (e), ACW-L plus ACW-R; (f), ACW-L plus ML-R; (g), ML-L plus CW-R; (h), ML-L plus ACW-R; (i), ML-L plus ML-R. The expected numbers of mice for each phenotype pair were calculated by multiplying the product of the two appropriate individual overall frequencies (CW = 0.455, ACW = 0.402 and ML = 0.143) by the number of pairs of eyes. For example, the expected number of mice with one CW and one ACW whorl is 0.455 × 0.402 × 56 = 10.25.
Mort et al. BMC Developmental Biology 2009 9:4 doi:10.1186/1471-213X-9-4