Table 3

Parameter estimates and likelihood scores for site models

Model

l (1)

Estimates of parameters (2)

l (3)

Positively selected sites (BEB) (4)


M0

-5729.43479

ω = 0.92

Not allowed


M1a

-5660.94116

ρ0 = 0.32

Not allowed


M2a

-5643.14631

ρ0 = 0.24, ρ1 = 0.53, ρs = 0.23, ωs = 2.08

35.59 *** (M2a vs M1a)

1 site p > 99%: 72Y, 9 sites p > 95%: 9V, 10T, 62R,

    73A
,
    75C
, 86A, 90E, 159R, 162Q


M7

-5661.09613

p = 0.64, q = 0.24

Not allowed


M8a

-5657.82124

ρ0 = 0.41, ρ1 = 0.59, p = 1.69, q = 3.62

Not allowed


M8

-5641.30866

ρ0 = 0.71, ρs = 0.29, p = 0.83, q = 0.44, ωs = 1.84

33.02 *** (M8 vs M8a)

9 sites p > 99%: 9V, 10T, 62R, 72Y,

    73A
,
    75C
, 86A, 90E, 162Q; 7 sites p > 95%: 6Q, 11S, 63K, 71F, 113G,
    119L
, 159R


Model

AICc score

Estimates of parameters (2)

Positively selected sites (BEB) (4)


M8a

18637.95571

p = 1.10, q = 1.73

Not allowed


MEC

18220.66368

p = 0.80, q = 2.56

5 sites p > 95%: 9V, 72Y,

    73A
, 90E, 163L


(1) Log- likelihood values.

(2) ωS: average dN/dS ratio for sites subject to positive selection (models M2a and M8), p and q: shape parameters for the beta distribution of ω (models M7, M8 and MEC). ρ0, ρ1, and ρS are the proportions of codons subject to purifying selection, neutral evolution, and positive selection, respectively.

(3) *** significant at p < 0.001.

(4) Bold: P > 95% for the three comparisons (M2a vs. M1a, M8 vs. M8a, MEC vs. M8a).

Italic: P > 95% for the two comparisons (M2a vs. M1a and M8 vs. M8a).

Underlined: amino acids involved in androstenol and androstenone binding.

Site numbers and amino acids refer to the pig SAL1 reference sequence PDB: 1GM6.

Meslin et al. BMC Evolutionary Biology 2011 11:148   doi:10.1186/1471-2148-11-148

Open Data