Port wine stain (PWS) is a congenital vascular malformation of human skin involving the superficial vascular plexus, occurring in an estimated 3–5 children per 1,000 live births. 1 A sporadic somatic guanine nucleotide-binding protein, G alpha subunit q (GNAQ) mutation (R183Q) has been identified in PWS lesions. 2, 3 However, the cell-type specific distributions of the GNAQ mutation (R183Q) in PWS lesions have yet to be determined.

The study was approved by the Institutional Review Board at the University of California, Irvine. The clinical histories of PWS biopsy samples were described in a previous study. 4 In order to identify which skin structure enriches the GNAQ (R183Q), we performed laser capture microscopy (LCM) to collect blood vessels and three other structures within PWS lesional skin, namely, epidermis, hair follicles/glands and connective tissues, on formalinfixed paraffin embedded (FFPE) sections. An outline of LCM and DNA library construction is illustrated in Figure 1.