Alu sequence alignment. The consensus sequence for the Alu Y subfamily is shown at the top, with western lowland gorilla-specific Alu subfamilies listed below. The dots below the consensus denote the same base with insertions and deletions noted by dashes and mutations with the appropriate bases. The consensus sequences for the Alu Ya1, Alu Yc1, and Alu Yc5 subfamilies included for comparative purposes. Subfamily-specific diagnostic mutations are highlighted in yellow. Lineage-specific deletions are highlighted in red. Alu Y_Gorilla is 100% identical to the Alu Y consensus sequence. The shared 12-bp deletion identifying the Alu Yc5-derived Gorilla subfamilies is located at position 86. The 16-bp and 20-bp deletions identifying the Alu Y16_Gorilla and Alu Y16a4_Gorilla subfamilies are visible at positions 228 and 232.