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BackgroundTo date, only a small portion of the genetic variation for primary open-angle glaucoma (POAG), the major type of glaucoma, has been elucidated.Methods and Principal FindingsWe examined our two data sets of the genome-wide association studies (GWAS) derived from a total of 2,219 Japanese subjects. First, we performed a GWAS by analyzing 653,519 autosomal common single-nucleotide polymorphisms (SNPs) in 833 POAG patients and 686 controls. As a result, five variants that passed the Bonferroni correction were identified in CDKN2B-AS1 on chromosome 9p21.3, which was already reported to be a significant locus in the Caucasian population. Moreover, we combined the data set with our previous GWAS data set derived from 411 POAG patients and 289 controls by the Mantel-Haenszel test, and all of the combined variants showed stronger association with POAG (P<5.8×10−10). We then subdivided the case groups into two subtypes based on the value of intraocular pressure (IOP)—POAG with high IOP (high pressure glaucoma, HPG) and that with normal IOP (normal pressure glaucoma, NPG)—and performed the GWAS using the two data sets, as the prevalence of NPG in Japanese is much higher than in Caucasians. The results suggested that the variants from the same CDKN2B-AS1 locus were likely to be significant for NPG patients.Conclusions and SignificanceIn this study, we successfully identified POAG-associated variants in the CDKN2B-AS1 locus using a Japanese population, i.e., variants originally reported as being associated with the Caucasian population. Although we cannot rule out that the significance could be due to the differences in sample size between HPG and NPG, the variants could be associated specifically with the vulnerability of the optic nerve to IOP, which is useful for investigating the etiology of glaucoma.

The thermomagnetic curves of the ferromagnetic Sm intermetallics, polycrystalline samples of the CsCl-type compounds SmZn and SmCd, and a single crystal of the cubic Laves phase compound SmAl 2 , have been measured in a temperature range from 2 to 300 K, and the exotic behavior has been well explained with the model of Sm 3ϩ in a metallic matrix. The M -T curves in the ordered states for these compounds, just like those of ferrimagnets, reflect the different temperature dependences of the spin moment and the orbital one, which is due mainly to the thermal variation of the admixture among the J multiplets of the 4 f electrons through the exchange field. Utilizing this property, the separation of the 4 f -spin, 4 f -orbital, and conduction-electron component from the total ordered moment has been successfully done. Some microscopic properties of these compounds, such as the difference between the conduction-electron polarization effect in the ordered state and that in the paramagnetic one, have been also suggested through the analysis.