Spatial and temporal TLR3 variation across islands
No significant deviation from HWE was observed in any of the different
island populations, either pre- or post- translocation (Table S4). All
populations showed the same overall trend, withTLR3 C alleles decreasing in frequency over time
(Fig 4), but the rate of change differed between islands (Table 3, Fig
4). As shown above, TLR3 C allele frequencies on
Cousin were significantly lower in 2018 compared to 1993-94 (P<0.001, Table 3, Fig 4). Of the translocated populations, only
Denis showed a significant decline in TLR3 Callele frequency between the initial and most recent sample (15 years
difference; P = 0.002; Fig 4; Table 3). TLR3 allele
frequency temporal differences for Frégate (7 years difference), and
between the oldest samples from the source population (Cousin) and the
contemporary samples from Aride and Cousine (20 or 28-year difference
respectively) were not significant (Fig 4; Table 3).
Focusing on the most recent samples, we found significant TLR3differentiation between Denis and Aride (P = 0.001; Table 3),
Denis and Cousine (P = 0.009; Table 3), and Aride and Cousin
(P = 0.022; Table 3). Denis had the lowest frequency ofTLR3 C alleles (22%) while Aride had the
highest (39%) (see Fig 4). All other pairwise comparisons were not
significant (Table 1).