In four cases, these links come from studies in lung tissue: DNA methylation changes in ABCA1 in lung tissue has been reported to be associated with pulmonary arterial hypertension; differential expression of ABCA1 and DNAH9 has been reported in lung tissue of patients with COPD and primary ciliary dyskinesia respectively and pathological changes in lung tissue have been reported following knockdown and knockout of SLAMF7, ABCA1, and SOCS3. This evidence concerns the gene ABCA1 and pulmonary arterial hypertension.