Relative positions of FCGR2A, HSPA6, and FCGR3A genes on chromosome 1 long arm. Boxes represent coding exons; thin lines, coding introns; and heavy lines, intergenic regions. Gene names are indicated above DNA with transcription direction (arrows). Genes and intergenic lengths (dashed arrows), based on where translation starts and ends, are indicated as base pairs below DNA, using AL5990385.22 GenBank sequence of RP11-5K23 BAC clone and identifying genes by nucleotides identity with GenBank cDNA sequences NM 021642, NM 002455, and NM 000569, respectively.