Gene expression variation in African and European populations of Drosophila melanogaster

Table 2 Expression polymorphism by population

	Polymorphic probes		Mean pairwise differences per probe in %^†
	Total number (%)	Mean per PW (SD)*
Overall	1,894 (37.5%)	138.0 (53.0)	2.73
Europe	964 (19.1%)	126.5 (43.7)	2.51
Africa	1,039 (20.6%)	125.9 (47.8)	2.49
Between	1,600 (31.7%)	148.4 (57.3)	2.94

*Average number and standard deviation (SD) of probes found to be differentially expressed for each pairwise (PW) comparison between all strains within the corresponding data set.
^†Average percentage of pairwise comparisons showing differential expression for a probe.

ISSN: 1474-760X