Genetic association study of a single nucleotide polymorphism of kallikrein-related peptidase 2 with male infertility / 대한생식의학회지

OBJECTIVE: To investigate a kallikrein-related peptidase 2 (KLK2) single nucleotide polymorphism (SNP) in relation to male infertility because of its role in semen processing. We investigated the genetic association of the KLK2+255G>A genotype with male infertility. METHODS: We genotyped the SNP site located in intron 1 (+255G>A, rs2664155) of KLK2 from 218 men with male infertility (cases) and 220 fertile males (controls). Pyrosequencing analysis was performed for the genotyping. RESULTS: The SNP of the KLK2 gene had a statistically significant association with male infertility (p<0.05). The odds ratio for the minor allele (+255A) in the pooled sample was 0.47 (95% confidence intervals, 0.26-0.85) for rs2664155. CONCLUSION: The relationship of KLK2 SNP to male infertility is statistically significant, especially within the non-azoospermia group. Further study is needed to understand the mechanisms associated with male infertility.

The Rapid Establishment of Human Clonal Adipose Derived Stem Cell (hADSC) Lines with Aspirated Adipose Tissue

PURPOSE: This study aims to establish a new strategy that provides for the rapid establishment of human clonal adipose derived stem cell (hADSC) lines with aspirated adipose tissue and to characterize newly generated hMSC lines for their cell phenotype, differentiation potential, lineage-specific gene expression. METHODS: Human adipose tissue-derived stem cells (hADSCs) were isolated from subcutaneous adipose tissue based on standard protocols. After incubation for 2 h, only the cell culture supernatant was transferred to a new dish. This process was repeated several times with 30 h incubations. RESULTS: We confirmed the difference in growth rate, however, differences were not seen in the differentiation capabilities and stemness of the each cell lines. CONCLUSION: It is necessary to establish cell lines via single cell level for application to disease specific tissue engineering.

Single Nucleotide Polymorphism in the Promoter Region of H1 Histone Family Member N, Testis-specific (H1FNT) and Its Association Study with Male Infertility

The H1 histone family, member N, testis-specific (H1FNT) is exclusively expressed in the testis, and had its possible role for sperm chromatin formation. The purpose of this study is to investigate any genetic association of H1FNT gene with male infertility, especially at the promoter region. We examined the promoter single nucleotide polymorphisms (SNP) of H1FNT gene which is located within transcription factor binding site for its association with male infertility. The statistical analysis showed that the -1129A>T polymorphism was present at a statistically significance in male infertility (p=0.0059 and 0.0349 for hetero and risk type, respectively). The dual-luciferase promoter assay was performed to examine the polymorphic effect of this promoter SNP by the cloning of promoter region (1700bp fragment) into pGL3-basic vector. In our plasmid based reporter system, there is no big difference between wild and risk type. In conclusion, H1FNT -1129A>T promoter SNP is statistically significant with male infertility, especially with subfertile (non-azoospermia) group. Further analysis of its functional polymorphic effect in vivo may provide the biological significance of testis-specific histone with spermatogenesis.

The Associtation between Methylenetetrahydrofolate Reductase Gene Polymorphisms and a Risk of Spontaneously Aborted Embryos / 대한불임학회지

OBJECTIVE: This study was performed to understand the influence of the methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) genotypes on the spontaneously aborted embryos. METHODS: DNA was extracted from tissue samples of 95 spontaneously aborted embryos and 100 samples of normal children randomly and 449 samples of normal adults were selected as the controls. MTHFR genotypes were determined by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. RESULTS: The aborted embryo group had higher frequency of MTHFR 677CC type (p=0.014) and lower 677CT type (p=0.063) than the controlled child group. The frequency of MTHFR 677CT type was drastically lower than that of controlled adult group (p=0.032). In the MTHFR C677T/A1298C combination, 677CC/1298AC genotype of the aborted embryo was significantly higher (p=0.034) than that of controlled child group, but it was not statistically significant in controlled adult group (p=0.063). CONCLUSION: MTHFR 677CC and MTHFR 677CC/1298AC genotypes may represent genetic markers for the risk of spontaneously aborted embryos at least in Koreans.

X-linked Gene Expression Profiles by RNAi-Mediated BRCA1 Knockdown in MCF7 Cells

Germ-line mutations of the BRCA1 gene confer an increased risk for breast and ovarian cancers. BRCA1 in female cells is directly related with the maintenance of the inactive X chromosome (Xi). The effect by the loss of the BRCA1 function on the X chromosome gene expression remains unclear in cancer cells. We attempted to investigate the expression pattern of the X-linked genes by performing BRCA1 knockdown via RNA interference in the MCF 7 breast cancer cell line. The transcriptional and translational levels of BRCA1 were decreased over 95% in the MCF 7 cells after BRCA1 knockdown. The expression patterns of one hundred ninety X-linked genes were profiled by the X chromosome-specific cDNA arrays. A total of seven percent of the X-linked genes (14/190) were aberrantly expressed by over 2-fold in the MCF7-BRCA1 knockdown cells, which contained two up-regulated genes (2/190, 1%) and 12 downregulated genes (12/190, 6.3%). It is interesting that 72% of the aberrantly expressed X-linked genes were located on the Xq (10/14,) region. Our data suggests that BRCA1 may not be important to maintain X chromosome inactivation in cancer because the BRCA1 knockdown did increase the expression of the only one percent of X-linked genes in the human breast cancer cells.

Gene Expression Analysis of Cultured Amniotic Fluid Cell with Down Syndrome by DNA Microarray

Complete or partial triplication of human chromosome 21 results in Down syndrome (DS). To analyze differential gene expressions in amniotic fluid (AF) cells of DS, we used a DNA microarray system to analyze 102 genes, which included 24 genes on chromosome 21, 28 genes related to the function of brain and muscle, 36 genes related to apoptosis, 4 genes related to extracellular matrix, 8 genes related to other molecular function and 2 house-keeping genes. AF cells were collected from 12 pregnancies at 16-18 weeks of gestation in DS (n=6) and normal (n=6) subjects. Our DNA microarray experiments showed that the expressions of 11 genes were altered by at least 2-folds in DS, as follows. Ten genes, COL6A1, CASP5, AKT2, JUN, PYGM, BNIP1, OSF-2, PRSS7, COL3A1, and MBLL were down-regulated and GSTT1 was only up-regulated. The differential expressions of GSTT1 and COL3A1 were further confirmed by semi-quantitative RT-PCR for each sample. The gene dosage hypothesis on chromosome 21 may explain the neurological and other symptoms of DS. However, our results showed that only two genes (COL6A1 and PRSS7), among 24 genes on chromosome 21, were down-regulated in the AF cells of DS. Our data may provide the basis for a more systematic identification of biological markers of fetal DS, thus leading to an improved understanding of pathogenesis for fetal DS.

Identification of New Proteins in Follicular Fluid from Mature Human Follicles by Direct Sample Rehydration Method of Two-Dimensional Polyacrylamide Gel Electrophoresis

Human follicular fluid (HFF) includes various biologically active proteins which can affect follicle growth and oocyte fertilization. Thus far, these proteins from mature follicles in human follicular fluid have been poorly characterized. Here, two-dimensional polyacrylamide gel electrophoresis (2-DE) with matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was used to identify new proteins in HFF. Mature follicular fluids were obtained from five females after oocyte collection during in vitro fertilization (IVF). We directly rehydrated HFF samples, obtained high-resolution 2-DE maps, and processed them for 2-DE and MALDI-MS. One hundred eighty spots were detected and 10 of these spots were identified. By the 2-DE database, six of them had been reported, as proteins already existing in HFF. Hormone sensitive lipase (HSL), Unnamed protein product 1 (UPP1), Unnamed protein product 2 (UPP2), and apolipoprotein A-IV precursor were newly detected. HSL and apolipoprotein A-IV participate in lipid metabolism. UPP1 has a homology with selenocysteine lyase. We found by RT-PCR that these genes are expressed from human primary granulosa cells. The proteins identified here may emerge as potential candidates for specific functions during folliculogenesis, hormone secretion regulation, or oocyte maturation. Further functional analysis of these proteins is necessitated to determine their biological implications.

The Study of X Chromosome Inactivation Mechanism in Klinefelter's Syndrome by cDNA Microarray Experiment

To investigate the XIST gene expression and its effect in a Klinefelter''s patient, we used Klinefelter''s syndrome (XXY) patient with azoospermia and also used a normal male (XY) and a normal female (XX) as the control, We were performed cytogenetic analysis, Y chromosomal microdeletion assay (Yq), semi-quantitative RT-PCR, and the Northern blot for Klinefelter''s syndrome (KS) patient, a female and a male control, We extracted total RNA from the KS patient, and from the normal cells of the female and male control subjects using the RNA prep kit (Qiagen), cDNA microarray contained 218 human X chromosome-specific genes was fabricated. Each total RNA was reverse transcribed to the first strand cDNA and was labeled with Cy-3 and Cy-5 fluorescein, The microarray was scanned by ScanArray 4000XL system. XIST transcripts were detected from the Klinefelters patient and the female by RT-PCR and Northern blot analysis, but not from the normal male, In the cDNA microarray experiment, we found 24 genes and 14 genes are highly expressed in KS more than the normal male and females, respectively. We concluded that highly expressed genes in KS may be a resulted of the abnormal X inactivation mechanism.

Contribution of Thymidylate Synthase Enhancer Region (TSER) Polymorphism to Total Plasma Homocysteine Levels in Korean Patients with Recurrent Spontaneous Abortion / 대한불임학회지

OBJECTIVES: Methylenetetrahydrofolate reductase (MTHFR) mutation are commonly associated with hyperhomocysteinemia, and through their defects in homocysteine metabolism, they have been implicated as a risk factor for recurrent spontaneous abortion. Recent report describe that 28-bp tandem repeat polymorphism in thymidylate synthase enhancer region (TSER) that influence enzyme activity would affect plasma homocysteine level. We have investigated the relationship between TSER genotype and plasma homocysteine level in 54 patients with recurrent spontaneous abortion. METHODS: Plasma homocysteine level was measured by fluorescent polarizing immunoassay. MTHFR mutation (C677T and A1298C) was identified by PCR-restriction fragment length polymorphism assay and TSER mutation was analyzed by PCR method. The data were analyzed using the program SAS 8.2 for Windows. RESULTS: Total homocysteine level was significantly higher in MTHFR 677TT genotype (9.80+/-3.87 mumol/L) than MTHFR 677CC genotype (8.14+/-1.74 mumol/L) in Korean patients with unexplained recurrent spontaneous abortion (p=0.0143). However, the plasma homocysteine level was not significantly different in the MTHFR 1298AA (8.42+/-2.65 mumol/L) and 1298CC (6.09+/-0.32 mumol/L; p=0.2058) and, TSER 2R2R (8.61+/-1.68 mumol/L) and 3R3R (8.05+/-2.81 mumol/L; p=0.9319) mutant genotypes, respectively. In this study, we found the combination effects of TSER and MTHFR C677T genotypes. Plasma homocysteine levels were the highest (11.47+/-4.66 mumol/L) in individuals with TSER 3R3R (8.05+/-2.81 mumol/L) and MTHFR 677TT (9.80+/-3.87 mumol/L) genotypes. Individuals with a combination of both TSER 2R2R/2R3R and MTHFR 677CC/CT genotypes (7.69+/-1.77 mumol/L) had lower plasma homocysteine levels than TSER 2R2R (8.61+/-1.68 mumol/L) and MTHR 677CC (8.14+/-1.74 mumol/L) genotypes, respectively. The effect of MTHFR polymorphism in the homocysteine metabolism appears to be stronger than that of TSER polymorphism. CONCLUSION: Although statistically not significant, we found the elevated level of plasma homocysteine in combined genotypes with TSER and MTHFR (C677T and A1298C) in Korean patients with unexplained habitual abortion. In this study, we reported the possibility that TSER polymorphism is a genetic determinant of plasma homocysteine levels in the Korean patients as well as MTHFR C677T polymorphism. A large prospective study is needed to verify our findings.

Application of DNA chip techniques for Yq microdeletion analysis in infertile males

Our aim was to apply DNA chip technology as a diagnostic tool in infertility research and clinics. Six loci, including a sex-determining region on the Y chromosome and five sequence-tagged sites in azoospermia-factor regions were investigated in infertile male patients. Our method produced a sensitive signal, which showed the presence or absence of the STS regions on the Y chromosome. The results from 93 patients with non- obstructive azoospermia, oligoathenoteratozoospermia, or oligozoospermia were identical when analyzed with either the DNA chip technique or conventional PCR-gel electrophoresis. We have demonstrated its application in the molecular diagnosis of male infertility. This system provides an economic and high-throughput method for detecting the deletion of genomic DNA sequences of large groups of infertile patients, and a completely new approach to male infertility screening. The application of DNA chip technology to identify Yq deletions can also facilitate our understanding of male infertility.

The Study of 5,10-Methylenetetrahydrofolate Reductase Variation (MTHFR C677T) in Infertile Females with Polycystic Ovarian Syndrome (PCOS) in Korea / 대한불임학회지

OBJECTIVE: To investigate the association of genetic background between MTHFR C677T genotype and infertile females with polycystic ovarian syndrome. MATERIALS AND METHODS: We compared 86 infertile females with polycystic ovarian syndrome (PCOS) with 100 healthy fertile females with one or more offspring. Pyrosequencing analysis for MTHFR C677T variation was performed on polymerase chain reaction (PCR) product of study group. To validate pyrosequencing data of C677T variation for randomly selected 50 samples, we compared the pyrosequencing result with the PCR-RFLP (Restriction Fragment Length Polymorphism) result of MTHFR C677T genotype. RESULTS: The prevalence of the C677T mutant homozygous (TT) was significantly lower (p=0.0085) in females with PCOS (8.14%) than in fertile females (21.00%). MTHFR 677 TT genotype had a decreased risk (3.7-fold) of PCOS compared with wild type (MTHFR 677 CC). CONCLUSION: Our data support a role for MTHFR mutant homozygous (677 TT) genotype in reducing risk in Korean infertile females with Polycystic ovarian syndrome.

Genetic analysis for Polymorphism of 5, 10-Methylenetetrahydrofolate Reductase (MTHFR) A1298C and Infertile Males in Korea / 대한불임학회지

OBJECTIVE: To investigate the association of genetic background between MTHFR A1298C genotype and male infertility. MATERIALS AND METHODS: We compared 377 infertile males with 396 healthy fertile males with one or more offspring. Infertile males were classified into four subtypes (281 azoospermia, 26 oligoasthenoteratozoospermia (OAT), 59 severe OAT and 11 remnants) by World Health Organization (WHO). Pyrosequencing analysis for MTHFR (methylenetetrahydrofolatereductase) A1298C variation was performed on polymerase chain reaction (PCR) product of study group. To validate pyrosequencing data of A1298C variation for randomly selected 50 samples, we compared the pyrosequencing result with the PCR-RFLP (Restriction Fragment Length Polymorphism) result of MTHFR A1298C genotype. RESULTS: We studied MTHFR A1298C variation by pyrosequencing. A1298C variation data (1298 AC; p=0.2166 and 1298 CC; p=0.5056) of MTHFR gene was no significant difference in between fertile and infertile males. CONCLUSION: The genetic analysis in MTHFR gene didn't appear genetic difference in Korean fertile and infertile males. We require further study for MTHFR gene in infertile males.

Polymorphisms of 5,10-Methylenetetrahydrofolate Reductase (MTHFR C677T and A1298C) Gene in Recurrent Spontaneous Abortion / 대한불임학회지

OBJECTIVE: Previous studies have suggested that hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR C677T) mutations are associated with increased risk of recurrent spontaneous abortion (RSA). Recently, a second site polymorphism in MTHFR, 1298A-->C, which changes a glutamic acid into an alanine residue, was shown to be associated with a decreased enzyme activity. We tested whether the variant alleles of MTHFR C677T and A1298C are risk factor (biomarker) for RSA. MATERIALS AND METHODS: We analyzed DNA from a case-control study in the Korean DNA was extracted from blood samples of 118 patients with RSA and 123 healthy fertile patients as the controls. MTHFR variant alleles were determined by a PCR-restriction fragment length polymorphism assay. RESULTS: We found no evidence for an association between 677TT genotype and risk of RSA (OR=1.95, 95% CI=0.84~4.50, p=0.12). However, the MTHFR 1298AC (OR=0.36, 95% CI=0.20~ 0.63, p=0.0004) and 1298AC+CC (OR=0.35, 95% CI=0.20~0.61, p=0.0002) genotypes were lower among 118 RSA cases compared with 123 controls, conferring a 2.8-fold decrease in risk of RSA, respectively. Moreover, the combined genotypes of MTHFR 677CC/1298AC (OR=0.30, 95% CI= 0.10~0.88, p=0.029) and 677CT/1298AC (OR=0.77, 95% CI=0.60~0.99, p=0.043) also showed significantly lower risk than those with MTHFR 677CC/1298AA type. CONCLUSION: MTHFR 1298AC, MTHFR 677CC/1298AC and 677CT/1298AC genotypes may represent genetic markers for the protection of RSA at least in Korean women.

The Analysis of SHP (Small Heterodimer Partner) Gene Mutation in Infertile Patients with Polycystic Ovary Syndrome (PCOS) in Korea / 대한불임학회지

OBJECTIVE: We inversigated Small Heterodimer Partner (SHP) gene mutation in Korean Polycystic Ovarian Syndrome (PCOS) patients. SHP protein regulates the activity of nuclear receptors which regulate the cellular development and differentiation. Recently, the mutation of SHP gene was found in the obesity and diabetes patients in Japanese group, and suggested that its mutation may involved in pathogenic mechanism of PCOS. METHODS: This study was performed in 20 PCOS patients and 20 normal women. The DNAs were extracted from the peripheral bloods, and amplified at each exon (1 and 2) of SHP gene by PCR method. Subsequently, each PCR product was digested with the restriction enzyme indicated below for studying restriction fragment length polymorphism (RFLP). After enzyme digestion, the results of RFLP were compared PCOS patients with control women to find any sequence variation. RESULTS: We examined 9 regions of exon 1 with Msp I, Pvu II, Dde I and 3 regions of exon 2 with Pst I, Dde I. There is no heterozygous or homozygous mutation in patients and control women at these restriction sites. CONCLUSION: The genetic analysis at our restriction sites in the SHP gene did not show any genetic variation in Korean PCOS patients. Our PCR-RFLP analysis was not covered the entire SHP gene (68 bp/ 1,006 bp), we need to further analysis of the entire SHP gene.