Figure 4.

A chromosome map showing the location of markers that were homozygous in all 3 affected children (as horizontal bars) in the initial 5-cM genome-wide scan. Consecutive homozygous markers on chromosomes 2p (D2S2369, D2S337, and D2S2368), 2q (D2S2188 and D2S364), and 21p (D21S1904 and D21S1911) are highlighted by boxes. The approximate locations of all complex I subunit genes are shown in black text, and those subunit genes located adjacent to homozygous regions from the genome-wide scan are shown in bold italicized text. The prefix “NDU” is omitted from subunit gene names for clarity. The locations of the 7 most downregulated genes in both patients compared with control as revealed by microarray analysis are shown by gray underlined text. NDUFS6 is highlighted by an ellipse, as it was the only subunit gene located adjacent to a homozygous region that showed significant underexpression on microarray analysis.