Table 2. Endogenous Elba2 and His1 exhibit synthetic lethal genetic interactions.

Cross	Viability	p-value
+; Tub-GAL4/TM3,Sb × +; pINT-H11M/TM3, Sb	17/135 (68), 25%	N/A
Elba21; Tub-GAL4/TM3,Sb × Elba21; pINT-H11M/TM3, Sb	8/235 (118), 7%	7.0 · 10-4

All crosses were performed at 26 °C. In a control cross, heterozygous males that carry the Tub-GAL4 driver on the III chromosome balanced with TM3, Sb were mated to females that carry pINT-1-H1^1M His1 RNAi allele balanced with TM3, Sb. In the experimental cross, the parents additionally carried a homozygous Elba2¹ allele on the II chromosome. Viability of the progeny was scored as the number of eclosed Sb+ adults relative to the total number of offspring (column 2). The expected numbers of Sb+ flies (calculated from the Mendelian distribution) are shown in parentheses; percent viability relative to the expected numbers is also shown. Probability value is calculated by the chi-square two-way test (column 3). Elba2 mutation enhances the H1 depletion-dependent semilethal effect in a statistically significant fashion. N/A, not applicable.