Kawasaki disease is a systemic vasculitis of unknown etiology, with clinical observations suggesting a substantial genetic contribution to disease susceptibility. We conducted a genome-wide association study and replication analysis in 2,173 individuals with Kawasaki disease and 9,383 controls from five independent sample collections. Two loci exceeded the formal threshold for genome-wide significance. The first locus is a functional polymorphism in the IgG receptor gene FCGR2A (encoding an H131R substitution) (rs1801274; P = 7.35 × 10(-11), odds ratio (OR) = 1.32), with the A allele (coding for histadine) conferring elevated disease risk. The second locus is at 19q13, (P = 2.51 × 10(-9), OR = 1.42 for the rs2233152 SNP near MIA and RAB4B; P = 1.68 × 10(-12), OR = 1.52 for rs28493229 in ITPKC), which confirms previous findings(1). The involvement of the FCGR2A locus may have implications for understanding immune activation in Kawasaki disease pathogenesis and the mechanism of response to intravenous immunoglobulin, the only proven therapy for this disease.

Background-Fabry disease is a treatable lysosomal storage disorder, which is often misdiagnosed or belatedly diagnosed. Methods and Results-To determine the disease incidence in the Taiwan Chinese population, a Fabry disease newborn screening study was initiated. A total of 110 027 newborns were screened by assaying the ␣-galactosidase A (␣-Gal A) activity using dry blood spots. Low plasma ␣-Gal A activity and presence of a Fabry mutation was demonstrated in 45 neonates (3 females). Eight different mutations were identified, including 3 known missense mutations (R112H, A143T, and R356W), 4 novel missense mutations (G104V, M296L, G360C, and K391T), and one known intronic mutation (IVS4ϩ919G3 A). The IVS4ϩ919G3 A mutation was most common (82% of patients). A total of 20 maternal grandparents of infants harboring this intronic mutation were evaluated by echocardiography, mutation analysis and ␣-Gal A activity assay. The intronic mutation was found in 9 grandfathers and 11 grandmothers. Of these grandparents, 3 grandfathers (33%) but none of the grandmothers had hypertrophic cardiomyopathy. Additionally, 16 males who had been diagnosed with idiopathic hypertrophic cardiomyopathy were screened by mutation analysis and ␣-Gal A activity; 4 (25%) showed deficient plasma ␣-Gal A activity in combination with the intronic mutation. Conclusion-We found an unexpected high prevalence of the cardiac variant Fabry mutation IVS4ϩ919G3 A among both newborns (Ϸ1 in 1600 males) and patients with idiopathic hypertrophic cardiomyopathy in the Taiwan

Infants younger than 6 months with prolonged unexplained febrile illnesses should be suspected as having Kawasaki disease, despite the incomplete clinical presentation. Because early diagnosis and timely treatment are difficult in younger infants with Kawasaki disease because of delayed and incomplete clinical presentations, echocardiogram becomes an important implement for diagnosis. Early intravenous immunoglobulin treatment is required in view of the highest risk of coronary involvement in them.