Terrestrial n-alkanes and their carbon isotope records from the Hanon paleo-maar sediment, Jeju Island, Korea: Implications for paleoclimate and paleovegetation over the last 35 kyrs

Hyun, S.,Shin, K.H.,Lee, S.C.,Chang, S.W.,Nam, S.I. Pergamon Press 2017 QUATERNARY INTERNATIONAL Vol.441 No.1

<P>The carbon isotope of total carbon (delta C-13(org)), long-chain n-alkanes, and their compound-specific carbon isotope ratios (delta C-13(ALK)) were investigated in the Hanon paleo-maar sediment, Jeju Island of Korea to understand paleoclimate variabilities and their paleovegetation linkages. Based on the organic geochemical data (TOC (%), TN (%), and their delta C-13(org) and delta N-15), the core column stratigraphy was divided into three units, namely from the bottom to 14.5 ka (Unit I), from 14.5 ka to 3.01<a (Unit II), and from 3.0 ka to the core top (Unit III), respectively. In particular, delta C-13(org) showed marked fluctuation from -17.31%o to -28.68%o, suggesting different organic carbon sources. A relatively narrow range of variation in delta C-13(org) was observed in Unit III, and drastic changes in delta C-13(org) were observed from Unit I to Unit II. This may indicate a predominance of C-4 plants in Unit I, and drastic changes from terrestrial C-4 to C-3 in Unit II and predominance of C-3 plants in Unit III. The distributions of n-alkane were characterized by a continuous predominance of odd-numbered n-alkanes, particularly nC(29) and nC(31), and by high fluctuation of the total n-alkanes concentration. The average chain length (ACL), carbon preferences index (CPI), and paleoplant proxy (Paq) showed high fluctuation and glacial-interglacial variations with distinctive a high and low ratio at about 9.2 ka, corresponding to the switching points of delta C-13(org) and a high concentration of nalkane distribution. Individual n-alkane odd-numbered isotopes of delta C-13(Auc) ranged between -11.80%o in delta C-13n(21) and -34.93%o in delta C-13n(31), suggesting different sources of n-alkanes. The distribution of n-alkanes and their individual delta C-13(Auc), in particular delta C-13n(21), support paleovegetation changes, and their time dependent variations matched well with glacial-interglacial paleoclimate variations. Therefore, organic geochemical proxies recorded in Hanon paleo-maar sediment reflects paleoclimate variabilities as well as paleovegetation changes for the last 35 kyr in Jeju Island, Korea. (C) 2016 Elsevier Ltd and INQUA. All rights reserved.</P>

오대산 소나무림의 유기탄소 분포 및 수지

장미나 ( Mi Na Jang ),김성용 ( Sung Yong Kim ),( Azyleah C. Abino ),김창현 ( Chang Hyun Kim ),이중효 ( Jung Hyo Lee ),이영진 ( Young Jin Lee ) 한국임학회 2014 산림과학 공동학술대회 논문집 Vol.2014 No.-

본 연구는 백두대간에 위치하고 있는 오대산 국립공원 소나무림을 대상으로 2012년 6월부터 2013년 5월까지 지상부와 지하부 현존량, 낙엽생산량, 낙엽층의 낙엽량과 토양의 유기탄소 분포를 조사하였으며, 탄소수지를 파악하기 위하여 토양호흡을 측정하였다. 오대산 소나무림에서 조사된 총 유기탄소량은 230.11 ton C/ha으로, 지상부와 지하부의 유기탄소량은 각각 182.78 ton C/ha, 45.70 tonC/ha이었으며, 낙엽층과 토양의 유기탄소량은 각각 5.98 ton C/ha, 45.40 ton C/ha이었다. 오대산 소 나무림에서 연간 광합성을 통하여 식물체에 고정되는 유기탄소량은 17.76 ton C/ha/yr로 임내 층위에 따라 유기탄소가 고정되어 있다. 또한 조사기간 동안 낙엽을 통하여 임상으로 유입되는 유기탄소 량은 3.233 ton C/ha/yr이었다. 토양호흡을 통하여 방출되는 탄소량은 5.76 ton C/ha/yr으로 이 중미생물호흡을 통해 방출되는 탄소량은 3.11 ton C/ha/yr이고, 뿌리호흡을 통하여 방출되는 탄소량은2.65 ton C/ha/yr이었다. 그 결과, 오대산 소나무림에서 연간 대기로부터 순 흡수하는 유기탄소는 14.65 ton C/ha/yr로 조사되었다. This study was conducted to estimate carbon sequestration and carbon budget of Pinus densiflora stands in the Mt. Odae National Park. Above and below ground standing biomass, litter layer, soil organic carbon, and soil respiration were measured to estimate the amount of carbon and the carbon budget from June 2012 through May 2013. Total amount of carbon was 230.11 ton C/ha attributed to above (182.78 ton C/ha) and below (45.70 ton C/ha) ground biomass, litter layer (5.98 ton C/ha) and soil organic carbon (45.40 ton C/ha). This was equivalent to 17.76 ton C/ha/yr from above and below ground biomass, shrub and herb. In addition, the amount of organic carbon returned to the forest through litterfall was 3.233 ton C/ha/yr. The amount of carbon evolved through soil respiration was 5.76 ton C/ha/yr to which 3.11 ton C/ha/yr was accounted for microbial respiration while the remaining 2.65 ton C/ha/yr was due to root respiration. Based on the estimation of the difference between Net Primary Production and microbial respiration, the amount of atmospheric carbon sequestered by Pinus densiflora stands was 14.65 ton C/ha/yr.

오대산 신갈나무림의 낙엽생산과 유기탄소 동태

장미나 ( Mi Na Jang ),김성용 ( Sung Yong Kim ),( Azyleah C. Abino ),김창현 ( Chang Hyun Kim ),이중효 ( Jung Hyo Lee ),이영진 ( Young Jin Lee ) 한국임학회 2014 산림과학 공동학술대회 논문집 Vol.2014 No.-

본 연구는 백두대간에 위치하고 있는 오대산 국립공원 신갈나무림을 대상으로 2012년 6월부터 2013년 5월까지 지상부와 지하부 현존량, 낙엽생산량, 낙엽층의 낙엽량과 토양의 유기탄소 분포를 조사하였으며, 탄소수지를 파악하기 위하여 토양호흡을 측정하였다. 오대산 신갈나무림에서 조사된 총유기탄소량은 93.07 ton C/ha으로, 지상부와 지하부의 유기탄소량은 각각 72.36 ton C/ha, 18.09 tonC/ha이었으며, 낙엽층과 토양의 유기탄소량은 각각 4.39 ton C/ha, 42.28 ton C/ha이었다. 오대산 신갈나무림에서 연간 광합성을 통하여 식물체에 고정되는 유기탄소량은 5.46 ton C/ha/yr로 임내 층위에 따라 교목층 4.26 ton C/ha/yr, 관목층 0.24 ton C/ha/yr, 초본층 0.95 ton C/ha/yr의 유기탄소가 고정되어 있다. 또한 조사기간 동안 낙엽을 통하여 임상으로 유입되는 유기탄소량은 2.840 tonC/ha/yr이었다. 토양호흡을 통하여 방출되는 탄소량은 5.52 ton C/ha/yr으로 이 중 미생물호흡을 통해 방출되는 탄소량은 2.98 ton C/ha/yr이고, 뿌리호흡을 통하여 방출되는 탄소량은 2.54 tonC/ha/yr이었다. 그 결과, 오대산 신갈나무림에서 연간 대기로부터 순 흡수하는 유기탄소는 2.48 tonC/ha/yr로 조사되었다. This study was conducted to estimate Litter Production and carbon budget of Quercus mongolica stands in the Mt. Odae National Park. Above and below ground standing biomass, litter layer, soil organic carbon, and soil respiration were measured to estimate the amount of carbon and the carbon budget from June 2012 through May 2013. Total amount of carbon was 93.07 ton C/ha attributed to above (72.36 ton C/ha) and below (18.09 ton C/ha) ground biomass, litter layer (4.39 ton C/ha) and soil organic carbon (42.28 ton C/ha). This was equivalent to 5.46 ton C/ha/yr where 4.26 ton C/ha/yr is from above and below ground biomass, 0.24 ton C/ha/yr from shrub and 0.95 ton C/ha/yr from herb. In addition, the amount of organic carbon returned to the forest through litterfall was 2.840 ton C/ha/yr. The amount of carbon evolved through soil respiration was 5.52 ton C/ha/yr to which 2.98 ton C/ha/yr was accounted for microbial respiration while the remaining 2.54 ton C/ha/yr was due to root respiration. Based on the estimation of the difference between Net Primary Production and microbial respiration, the amount of atmospheric carbon sequestered by Quercus mongolica stands was 2.48 ton C/ha/yr.

제주재래돼지와 듀록 참조축군에서 Melanocortin 4 Receptor (MC4R) 유전자형과 지방산 조성간의 관련성 분석

강용준(Yong-Jun Kang),김상금(Sang-Geum Kim),김수연(Su-Yeon Kim),신문철(Moon-Cheol Shin),우제훈(Jae-Hoon Woo),김남영(Nam-Young Kim),신상민(Sang-Min Shin),최재영(Jae-Young Choi),유지현(Ji-Hyun Yoo),박남건(Nam-Geon Park),양병철(Byoung-C 한국생명과학회 2020 생명과학회지 Vol.30 No.1

본 연구에서는 제주재래돼지와 듀록 품종 사이에서 생산된 F₂ 참조축군에서 melanocortin-4-receptor (MC4R) 유전자형과 지방산 조성간의 관련성을 연구하였다. 전체 290 여두의 F₂ 자손을 이용하여 14개의 지방산 조성을 측정하였다. Taq Ⅰ PCR-RFLP 방법을 이용하여 MC4R c.1426A>G (p.Asp298Asn)의 단일염기다형성(single nucleotide polymorphism, SNP)을 확인하였다. MC4R 세 가지 유전자형(AA, AB, BB)이 모두 발견되었고, 그 빈도는 각각 0.299, 0.542, 0.159로 확인되었다. AA 유전자형을 가진 개체에서 palmitic acid (C16:0, p<0.05), stearic acid (C18:0, p<0.01), eicosenoic acid (C20:1n9, p<0.05), saturated fatty acid (SFA, p<0.01) 함량이 GG 유전자형을 가진 개체보다 더 높은 것으로 확인되었다. 반면에 GG 유전자형을 가진 개체는 linoleic acid (C18:2n6, p<0.001), linolenic acid (C18:3n3, p<0.001), linolenic acid (C18:3n6, p<0.001), arachidonic acid (C20:4n6, p<0.001)과 같은 불포화지방산(unsaturated fatty acid) 함량이 AA 유전자형을 가진 개체보다 더 높은 것을 확인하였다. 제주재래돼지와 듀록 품종 사이에서 생산된 F₂ 참조축군에서 MC4R GG 유전자형이 포화지방산은 낮추고, 불포화지방산은 높이는 것으로 확인되었다. 본 연구 결과 MC4R의 유전적 다형성이 듀록과 제주재래돼지 교배 프로그램에서 육질향상과, 고기내의 지방산 함량을 조절할 수 있는 유전적 표지 인자로 활용될 수 있을 것이라 사료된다. This study was conducted to examine association between melanocortin-4-receptor (MC4R) genotypes and fatty acid (FA) composition in an F₂ intercross between Duroc and Jeju (South Korea) Native pigs (JNP). Fourteen FA composition traits were measured in more than 290 F₂ progeny population produced between Duroc and JNP. All experimental pigs were successfully genotyped for the MC4R c.1426A>G (p.Asp298Asn) single nucleotide polymorphism (SNP) by using Taq Ⅰ PCR-RFLP methods. We detected three MC4R genotypes, AA, AG, and GG with 0.299, 0.542, and 0.159 genotype frequencies, respectively. The MC4R AA genotype animals showed higher levels in palmitic acid (C16:0, p<0.05), stearic acid (C18:0, p<0.01), eicosenoic acid (C20:1n9, p<0.05), saturated fatty acid (SFA, p<0.01) than GG homozygotes, respectively. Whereas MC4R GG genotype showed higher values in linoleic acid (C18:2n6, p<0.001), linolenic acid (C18:3n3, p<0.001), linolenic acid (C18:3n6, p<0.001), arachidonic acid (C20:4n6, p<0.001) and unsaturated fatty acid (USFA, p<0.01) than AA pigs, respectively. The MC4R GG genotype was associated with increasing USFA and decreasing SFA in the F₂ progeny population produced between Duroc and JNP. Our finding suggests that the MC4R polymorphisms can be used as a valuable genetic marker for Duroc and JNP breeding programs to improve meat quality and to control FA compositions.

Flux and stable C and N isotope composition of sinking particles in the Ulleung Basin of the East/Japan Sea

Hyun Kwak, J.,Han, E.,Hwang, J.,Kim, Y.I.,Lee, C.I.,Kang, C.K. Pergamon Press 2017 Deep-sea research. Part II, Topical studies in oce Vol.143 No.-

Seasonal variability of sinking fluxes of total mass (TMF), particulate organic carbon and nitrogen (POC and PON) was examined using sinking particles collected from sediment traps during July 2011 to December 2011, and December 2012 to June 2013 at an offshore channel site; and from November 2013 to August 2014 at a nearshore slope site of the Ulleung Basin in the East/Japan Sea. δ<SUP>13</SUP>C and δ<SUP>15</SUP>N values of sinking particles were measured to elucidate the major export processes of POC and PON. Annual TMF (112-638gm<SUP>-2</SUP>yr<SUP>-1</SUP>) and fluxes of POC and PON (9.6-32.1gCm<SUP>-2</SUP>yr<SUP>-1</SUP> and 1.2-4.5gNm<SUP>-2</SUP>yr<SUP>-1</SUP>, respectively) in the Ulleung Basin corresponded to the upper limit of values reported for other open seas and oceans in the world. No great seasonal variability in both quantitative (TMF, and fluxes and contents of POC and PON) and qualitative (C/N ratios, and δ<SUP>13</SUP>C and δ<SUP>15</SUP>N values) estimates of vertical fluxes was observed, reflecting a steady standing stock of chlorophyll a in the upper part of water column. Furthermore, high contents of POC and PON and nearly constant δ<SUP>13</SUP>C and δ<SUP>15</SUP>N values in sinking particles collected in the sediment traps, indicate that primary production in the euphotic zone may be a good predictor of TMF and export flux of organic matter. In this regard, our pilot study points out the importance of high annual primary production and low water temperature (<1<SUP>o</SUP>C) beneath the 200-m water depth, which would enable more sinking particles to be preserved during export process by limiting microbial decomposition activity in the water column, in determining the high annual flux of sinking particles in the Ulleung Basin (UB). A simple stable isotope mixing model of sinking particles indicates that despite a slight seasonal variation, the contribution of intact phytoplankton to sinking organic flux is significant to the POC and PON flux in the UB. Further continuous time series sediment trap experiments are proposed to estimate the contribution of allochthonus sources such as lateral advection through resuspended clay mineral, and aeolian and terrestrial inputs to the sedimentary flux.

Airborne volatile aromatic hydrocarbons at an urban monitoring station in Korea from 2013 to 2015

Khan, Azmatullah,Szulejko, Jan E.,Kim, Ki-Hyun,Brown, Richard J.C. Elsevier 2018 Journal of environmental management Vol.209 No.-

<P><B>Abstract</B></P> <P>The concentrations of C<SUB>6</SUB>-C<SUB>10</SUB> volatile aromatic hydrocarbons (AHCs) in air were measured at an urban air quality monitoring station in Jong-Ro, Seoul, Korea, between 2013 and 2015. Their temporal patterns (e.g., diurnal, intraweek, daily) were assessed individually and collectively as groups of benzene, toluene, ethylbenzene, styrene, and xylene (BTESX); total aliphatic hydrocarbon (TALHC: C<SUB>2</SUB>-C<SUB>12</SUB>); total aromatic hydrocarbon (TARHC: C<SUB>6</SUB>-C<SUB>10</SUB>); and total hydrocarbon (THC: C<SUB>2</SUB>-C<SUB>12</SUB>). The highest mean AHC concentrations over the 3-year study (in ppb (v/v)) were observed for toluene (6.0 ± 4.3), followed by the xylenes (1.5 ± 1.3), ethylbenzene (0.85 ± 0.93), benzene (0.73 ± 0.77), and styrene (0.16 ± 0.30) nL/L. The mean ppbC ((v/v), nL∙atm∙C/nL∙atm) values for BTESX, TALHC, TARHC, and THC were 65.8, 113, 77.7, and 191 ppbC, respectively. For most AHC species (e.g., toluene, styrene, and BTESX), only weak seasonal trends were observed in contrast to temporally varying species like nitric oxide (NO) (e.g., 26.3 ppb (January–February) vs. 8.5 ppb (July–August) during weekdays in 2013). Furthermore, toluene and NO concentrations were much higher (up to a factor 3) on weekdays than on Sunday for most weeks. This might reflect reduced anthropogenic activities on Sunday.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Toluene was the major BTESX. </LI> <LI> Propane was major hydrocarbon in all 56 hydrocarbons. </LI> <LI> Toluene and NO has strong correlation. </LI> <LI> Both toluene and NO showed much higher working day levels compare to Sunday. </LI> </UL> </P>

Interleukin-18, transforming growth factor-β, and vascular endothelial growth factor gene polymorphisms and susceptibility to primary glomerulonephritis

Choi, H.-J.,Cho, J.-H.,Kim, J.-C.,Seo, H.-J.,Hyun, S.-H.,Kim, G.-H.,Choi, J.-Y.,Choi, H.-J.,Ryu, H.-M.,Cho, J.-H.,Park, S.-H.,Kim, Y.-L.,Han, S.,Kim, C.-D. Blackwell Publishing Ltd 2010 Tissue antigens Vol.76 No.4

<P>Several studies have showed an association of gene polymorphisms with the development of glomerulonephritis (GN). We investigated the effects of gene polymorphisms on the development of GN by analyzing polymorphisms in the interleukin (IL)-18, transforming growth factor (TGF)-β, and vascular endothelial growth factor (VEGF) genes in Korean patients with primary GN. The study included 146 normal subjects (controls) and 100 patients diagnosed with primary GN by kidney biopsy. The gene polymorphisms A-607C and G-137C in <I>IL-18</I>, C-509T and T869C in <I>TGF-</I>β<I>1</I>, and C-2578A and C405G in <I>VEGF</I> were investigated in DNA extracted from peripheral blood. Significant differences were observed between the GN and control groups in the genotype and allele frequencies of A-607C <I>IL-18</I> and C405G <I>VEGF</I>. The frequencies of the <I>IL-18</I>−607CC genotype [<I>P</I> = 0.001, odds ratio (OR) = 2.473] and the <I>VEGF</I> 405GG genotype (<I>P</I> = 0.001, OR = 2.473) were significantly increased in the GN group. The combination of <I>IL-18</I>−607CC+ and <I>VEGF</I> 405GG+ genotypes had a higher risk for developing GN in comparison with the combination of <I>IL-18</I>−607CC− and <I>VEGF</I> 405GG− genotypes (<I>P</I> < 0.001, OR = 8.642). In the haplotype analysis of the <I>IL-18</I> gene, the CG haplotype was significantly more frequent in the GN group than the control group (61.5% <I>vs</I> 46.9%, <I>P</I> = 0.002). These results show that the −607CC genotype of the <I>IL-18</I> gene and the 405GG genotype of the <I>VEGF</I> gene are associated with susceptibility to and the development of primary GN.</P>

C-H Bond Addition across a Transient Uranium-Nitrido Moiety and Formation of a Parent Uranium Imido Complex

Mullane, Kimberly C.,Ryu, Ho,Cheisson, Thibault,Grant, Lauren N.,Park, Ji Young,Manor, Brian C.,Carroll, Patrick J.,Baik, Mu-Hyun,Mindiola, Daniel J.,Schelter, Eric J. American Chemical Society 2018 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.140 No.36

<P>Uranium complexes in the +3 and +4 oxidation states were prepared using the anionic PN<SUP>-</SUP> (PN<SUP>-</SUP> = (<I>N</I>-(2-(diisopropylphosphino)-4-methylphenyl)-2,4,6-trimethylanilide) ligand framework. New complexes include the halide starting materials, (PN)<SUB>2</SUB>U<SUP>III</SUP>I (<B>1</B>) and (PN)<SUB>2</SUB>U<SUP>IV</SUP>Cl<SUB>2</SUB> (<B>2</B>), which both yield (PN)<SUB>2</SUB>U<SUP>IV</SUP>(N<SUB>3</SUB>)<SUB>2</SUB> (<B>3</B>) by reaction with NaN<SUB>3</SUB>. Compound <B>3</B> was reduced with potassium graphite to produce a putative, transient uranium-nitrido moiety that underwent an intramolecular C-H activation to form a rare example of a parent imido complex, [K(THF)<SUB>3</SUB>][(PN)U<SUP>IV</SUP>(═NH)[<SUP><I>i</I></SUP>Pr<SUB>2</SUB>P(C<SUB>6</SUB>H<SUB>3</SUB>Me)N(C<SUB>6</SUB>H<SUB>2</SUB>Me<SUB>2</SUB>CH<SUB>2</SUB>)]] (<B>4</B>). Calculated reaction energy profiles strongly suggest that a C-H insertion becomes unfavorable when a reductant is present, offering a distinctively different reaction pathway than previously observed for other uranium nitride complexes.</P> [FIG OMISSION]</BR>

Re-evaluation of the Optimum Dietary Vitamin C Requirement in Juvenile Eel, Anguilla japonica by Using L-ascorbyl-2-monophosphate

Bae, Jun-Young,Park, Gun-Hyun,Yoo, Kwang-Yeol,Lee, Jeong-Yeol,Kim, Dae-Jung,Bai, Sung-Chul C. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.1

This study was conducted to re-evaluate the dietary vitamin C requirement in juvenile eel, Anguilla japonica by using L-ascorbyl-2-monophosphate (AMP) as the vitamin C source. Five semi-purified experimental diets were formulated to contain 0 ($AMP_0$), 30 ($AMP_{24}$), 60 ($AMP_{52}$), 120 ($AMP_{108}$) and 1,200 ($AMP_{1137}$) mg AMP $kg^{-1}$ diet on a dry matter basis. Casein and defatted fish meal were used as the main protein sources in the semi-purified experimental diets. After a 4-week conditioning period, fish initially averaging $15{\pm}0.3$ g (mean${\pm}$SD) were randomly distributed to each aquarium as triplicate groups of 20 fish each. One of five experimental diets was fed on a DM basis to fish in three randomly selected aquaria, at a rate of 3% of total body weight, twice a day. At the end of the feeding trial, weight gain (WG) and specific growth rate (SGR) for fish fed $AMP_{52}$ and $AMP_{108}$ were significantly higher than those recorded for fish fed the control diet (p<0.05). Similarly, feed efficiency (FE) and protein efficiency ratio (PER) for fish fed $AMP_{52}$ were significantly higher than those for fish fed the control diet (p<0.05). Broken-line regression analysis on the basis of WG, SGR, FE and PER showed dietary vitamin C requirements of juvenile eel to be 41.1, 41.2, 43.9 and 43.1 (mg $kg^{-1}$ diet), respectively. These results indicated that the dietary vitamin C requirement could range from 41.1 to 43.9 mg $kg^{-1}$ diet in juvenile eel when L-ascorbyl-2-monophosphate was used as the dietary source of vitamin C.

Association of −31T>C and −511 C>T polymorphisms in the interleukin 1 beta ( <i>IL1B</i> ) promoter in Korean keratoconus patients

Kim, So-Hee,Mok, Jee-Won,Kim, Hyun-Seok,Joo, C.K. Molecular Vision 2008 Molecular vision Vol.14 No.-

<P><B>Purpose</B></P><P>To investigate the genetic association between unrelated Korean keratoconus patients and interleukin 1 alpha (<I>IL1A</I>), interleukin 1 beta (<I>IL1B</I>), and IL1 receptor antagonist (<I>IL1RN)</I> gene polymorphisms.</P><P><B>Methods</B></P><P>We investigated the association between <I>IL1A</I> (rs1800587, rs2071376, and rs17561), <I>IL1B</I> (rs1143627, rs16944, rs1143634, and rs1143633), and <I>IL1RN</I> (rs419598, rs423904, rs424078, and rs315952, variable number tandem repeat [VNTR]) polymorphisms in 100 unrelated Korean keratoconus patients. One hundred control individuals without any corneal disease were selected from the general population. Polymerase chain reaction (PCR) – restriction fragment length polymorphism (RFLP) analysis and direct sequencing were used to screen for genetic variations in the <I>IL1</I> gene cluster. Haplotypes for the <I>IL1</I> gene cluster were constructed using Haploview version 4.0.</P><P><B>Results</B></P><P>We analyzed a total of 12 polymorphic sites in the <I>IL1</I> gene cluster. Among them, the −511 (rs16944) and −31 (rs1143627) positions in the promoter region of <I>IL1B</I> were significantly different between patient and control groups. The C allele of rs16944 (−511C>T, p=0.022, odds ratio of risk [OR]=1.46, 95% confidence intervals [CI] 0.94<2.27) and the T allele of rs1143627 (−31T>C, p=0.025, OR=1.43, 95% CI 0.92<2.22) were associated with a significantly increased risk of keratoconus in Korean patients. Linkage of the two alleles, −31*C and −511*T, was associated with an increased risk for keratoconus with OR=2.38 (p=0.012, 95% CI=1.116–5.046). The *C/*A genotype of rs2071376 in <I>IL1A</I> intron 6 was significantly different between the keratoconus patients and control subjects (p=0.034, OR=0.59, 95% CI 0.32<1.11). Other polymorphisms did not show an association with keratoconus risk.</P><P><B>Conclusions</B></P><P>This is the first report of <I>IL1</I> gene cluster mutation screening in Korean keratoconus patients. Significant differences in allelic frequency of <I>IL1B</I> between keratoconus patients and the control group suggest that <I>IL1B</I> polymorphisms may play a role in the susceptibility of unrelated Koreans to develop keratoconus.</P>