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MicroRNAs (miRNAs) are small [∼21 nucleotide (nt)] non coding RNAs (ncRNAs) that regulate gene expression posttranscriptionally. About 3.0% of human genes encode for miRNAs, and up to 30.0% of human protein coding genes may be regulated by miRNAs. Currently, more than 2000 unique human mature microRNAs are known. MicroRNAs play a key role in diverse biological processes including development, cell proliferation, differentiation and apoptosis. These processes are commonly dysregulated in cancer, implicating miRNAs in carcinogenesis, where they act as tumor supressors or oncogenes. Several miRNAs are associated with breast cancer. Here we present our initial results of miRNA analyses of breast cancer tissues using quantitative real time-polymerase chain reaction (ReTi-PCR) (qPCR) involving stem-loop reverse transcriptase (RT) primers combined with TaqMan® PCR and miRNA microarray analysis.

Hepatitis C virus (HCV) is a major public health problem. It is a leading cause of chronic liver disease and the most common indication for liver transplantation. The therapy for eradication of HCV infection is successful in only 50.0-80.0% of patients and is highly dependent on the HCV genotype. Molecular detection and characterization of HCV in the Republic of Macedonia started in 1990. Since then, more than 4000 samples have been analyzed at the Research Centre for Genetic Engineering and Biotechnology (RCGEB) "Georgi D. Efremov," Skopje, Republic of Macedonia. The prevalence of HCV infections in the healthy population of the Republic of Macedonia was found to be 0.4%, while it varies between 23.0 and 43.0% in different at-risk groups of patients. The prevalence of HCV genotypes, according to associated risk factors in HCV infected patients from the Republic of Macedonia, was analyzed. We found genotype 1 to be predominant in a group of hemodialysis patients, while genotype 3 was predominant in intravenous (IV) drug users. Association of six polymorphisms in the Oligoadenylate synthetase (OASL)-like interferon-stimulated gene with a sustained virological response was also analyzed. Our preliminary results suggest that non ancestral alleles in four of the six studies polymorphisms in OASL gene are associated with sustained virological response among HCV infected patients in R. Macedonia.

The most significant and well characterized genetic risk factors for breast and/or ovarian cancer are germline mutations in the BRCA1 and BRCA2 genes. The BRCA1 and BRCA2 gene mutations strikingly increase breast cancer risk, suggesting that polymorphisms in these genes are logical candidates in seeking to identify low penetrance susceptibility alleles. The aim of this study was to initiate a screen for BRCA1/2 gene mutations in order to identify the genetic variants in the Republic of Macedonia, and to evaluate the association of several single nucleotide polymorphisms (SNPs) in these genes with breast cancer risk. In this study, we included 100 patients with invasive breast cancer from the Republic of Macedonia, classified according to their family history and 100 controls. The methodology included direct sequencing, single nucleotide primer extension method and multiplex ligation probe amplification (MLPA) analysis, all followed by capillary electrophoresis (CE) on an ABI PRISM™ 3130 Genetic Analyzer. We identified a total of seven carriers of mutations in the BRCA1/2 genes. None of the tested polymorphisms was associated with sporadic breast cancer risk, however, polymorphism rs8176267 in BRCA1 and N372H in BRCA2 showed an association with breast cancer risk in patients with at least one family member with breast cancer.

Seminal plasma is a potential source of biomarkers for many disorders of the male reproductive system including male infertility. The identification and characterisation of differentially expressed proteins in seminal plasma of man with normal and impaired spermatogenesis can help in the elucidation of the molecular basis of male infertility. We compared the protein expression profiles of seminal plasma from four different groups of men as follows: normozoospermic, asthenozoospermic, oligozoospermic and azoospermic groups, using two-dimensional differential gel electrophoresis (2-D DIGE). We found eight proteins with statistically significant increased expression in azoospermia compared with at least one of the other studied groups. The differentially expressed spots were fibronectin, prostatic acid phosphatase (PAP), proteasome subunit alpha type-3, beta-2-microglobulin, galectin-3-binding protein, prolactin-inducible protein and cytosolic nonspecific dipeptidase. Notably, PAP was increased in patients with azoospermia compared with that of all other groups. We have observed no statistically significant differences in protein expression between three of the groups: normozoospermic, oligozoospermic and asthenozoospermic. We suggest that the identified panel of proteins in our study especially PAP have a strong potential to be used as azoospermia markers. However, further investigations will be necessary to validate these markers in samples of larger and independent patient cohorts and to clarify their role in the pathogenesis of male infertility., (© 2012 Blackwell Verlag GmbH.)

Infertility is a major health problem today, affecting about 15% of couples trying to conceive a child. Impaired fertility of the male factor is causative in 20% of infertile couples and contributory in up to another 30%-40%. Based on association studies, an increasing number of gene polymorphisms have been proposed to modulate the efficiency of spermatogenesis. Here, we have investigated the possible association of 9 single-nucleotide polymorphisms (SNP) in 8 different genes-FASLG, JMJDIA, LOC203413, TEX15, BRDT, OR2W3, INSR, and TAS2R38--with male infertility. We analyzed a total of 136 men with idiopathic infertility (60 azoospermic and 76 oligozoospermic) and 161 fertile controls. Our study group included individuals of different ethnic origin: 93 of the infertile men were Macedonians, 32 were Albanians, and 11 were of other origin. The control group was composed of 125 Macedonian and 36 Albanian men. The methodology included multiplex polymerase chain reaction/SNaPshot analyses, followed by capillary electrophoresis on an ABI3130 Genetic Analyzer. Of the 9 SNPs evaluated, 3 are significantly associated (P < .05) with male infertility: SNPs rs5911500 in LOC203413, rs3088232 in BRDT, and rs11204546 in OR2W3. SNP rs5911500 showed the strongest association with infertility among Albanians (P = .0001), whereas rs3088232 was most significantly associated with azoospermia among Macedonians (P = .0082). Moreover, the frequency of co-occurrence of LOC203413 minor T allele with either homozygosity or heterozygosity for the BRDT minor G allele was significantly higher among both azoospermic (6 of 60 [10%]; P = .0057; odds ratio [95% confidence interval], 8.83 [1.73-45.08]) and oligozoospermic (10 of 76 [13.2%]; P = .0002; odds ratio [95% confidence interval], 12.04 [2.57-56.47]) men in comparison with fertile controls (2 of 161 [1.2%]).

Spontaneous abortion is a significant clinical problem of different etiologies. Certain thrombophilia gene mutations have been associated with an increased risk of spontaneous abortion. Also, mutations in folate-related genes can lead to abnormal chromosomal segregation during meiosis which is the most common cause of spontaneous abortion. We have developed a multiplex single-base extension reaction assay that allows simultaneous analysis of 10 different mutations in thrombophilia- and folate-related genes (Factor V Leiden G1691A, Factor V H1299R, Factor II G20210A, Factor XIII V34L, PAI-I -675 4G/5G, FGB -455G/A, MTHFR C677T, MTHFR A1298C, MTR A2756G, and MTRR A66G). Using this method we have studied 232 women who had a spontaneous abortion and 209 of their male partners. Prevalence of Factor II G20210A and Factor V H1299R mutations was significantly higher in the women than in their male partners (2.4% and 0.7%, respectively [p=0.0499] for the Factor II mutation and 9.3% and 5.7%, respectively [p=0.0485] for the Factor V mutation). The prevalence of MTHFR C677T, MTHFR A1298C, MTR A2756G, and MTRR A66G mutations did not differ between the studied groups. In conclusion, we have developed a rapid, simple, reliable, and inexpensive multiplex SNaPshot method for determination of 10 thrombophilic mutations that may result in spontaneous abortions.

β-Thalassemias and abnormal hemoglobin variants are among the most common hereditary abnormalities in humans. Molecular characterization of the causative genetic variants is an essential part of the diagnostic process. In geographic areas with high hemoglobinopathy prevalence, such as the Mediterranean region, a limited number of genetic variants are responsible for the majority of hemoglobinopathy cases. Developing reliable, rapid and cost-effective mutation-specific molecular diagnostic assays targeting particular populations greatly facilitates routine hemoglobinopathy investigations. We developed a one-tube single-nucleotide primer extension assay for the detection of eight common Mediterranean β-thalassemia mutations: Codon 5 (-CT); CCT(Pro)->C-, Codon 6 (-A); GAG(Glu)->G-G, Codon 8 (-AA); AAG(Lys)->-G, IVS-I-1 (G->A), IVS-I-6 (T->C), IVS-I-110 (G->A), Codon 39 (C->T), and IVS-II-745 (C->G), as well as the hemoglobin S variant beta 6(A3) Glu>Val. We validated the new assay using previously genotyped samples obtaining 100% agreement between independent genotyping methods. Our approach, applicable in a range of Mediterranean countries, offers a combination of high accuracy and rapidity exploiting standard techniques and widely available equipment. It can be further adapted to particular populations by including/excluding assayed mutations. We facilitate future modifications by providing detailed information on assay design.

The most common genetic causes of spermatogenic failure are sex chromosomal abnormalities (most frequently Klinefelter's syndrome) and deletions of the azoospermia factor (AZF) regions (AZFa, AZFb, and AZFc) of the Y chromosome. Several studies have proposed that partial AZFc deletions/duplications may be a risk factor for spermatogenic impairment. We describe a multiplex quantitative fluorescent-polymerase chain reaction (QF-PCR) method that allows simultaneous detection of these genetic causes and risk factors of male infertility. The 11-plex QF-PCR permitted the amplification of the amelogenin gene, four polymorphic X-specific short tandem repeat (STR) markers (XHPRT, DXS6803, DXS981, and exon 1 of the androgen receptor gene), nonpolymorphic Y-specific marker (SRY gene), polymorphic Y-specific STR marker (DYS448), and coamplification of DAZ/DAZL, MYPT2Y/MYPT2, and two CDY2/CDY1 fragments that allow for determination of the DAZ, MYPT2Y, and CDY gene copy number. A total of 357 DNA samples from infertile/subfertile men (n = 205) and fertile controls (n = 152) was studied. We detected 14 infertile males with sex chromosome aneuploidy (10 with Klinefelter's syndrome, 2 XX, and 2 XYY males). All previously detected AZF deletions, that is, AZFc (n8), AZFb (n1), AZFb + c (n1), gr/gr (n11), gr/gr with b2/b4 duplication (n3), and b2/b3 (n5), gave a specific pattern with the 11-plex QF-PCR. In addition, 32 DNA samples showed a pattern consistent with presence of gr/gr or b2/b4 and 4 with b2/b3 duplication. We conclude that multiplex QF-PCR is a rapid, simple, reliable, and inexpensive method that can be used as a first-step genetic analysis in infertile/subfertile patients.

Spinal muscular atrophy (SMA) is the second most common lethal autosomal recessive disorder of childhood, affecting approximately 1 in 6,000-10,000 births, with a carrier frequency of 1 in 40-60. There is no effective cure or treatment for this disease. Thus, the availability of prenatal testing is important. The aim of this study was to establish an efficient and rapid method for prenatal diagnosis of SMA and genetic counseling in families with risk for having a child with SMA. In this paper we present the results from prenatal diagnosis in Macedonian SMA families using direct analysis of fetal DNA. The probands of these families were previously found to be homozygous for a deletion of exons 7 and 8 of SMN1 gene. DNA obtained from chorionic villas samples and amniocytes was analyzed for deletions in SMN gene. SMN exon 7 and 8 deletion analysis was performed by polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). Of the 12 prenatal diagnoses, DNA analysis showed normal results in eight fetuses. Four of the fetuses were homozygote for a deletion of exons 7 and 8 of SMN1. After genetic counseling, the parents of the eight normal fetuses decided to continue the pregnancy, while in the four families with affected fetuses, the pregnancy was terminated. The results were confirmed after birth.

Y chromosome deletions in the three azoospermia factor (AZF) regions constitute the most common genetic cause of spermatogenic failure. The aim of this study was to estimate the length and boundaries of the AZF deletions and to correlate the AZF deletions with the sperm concentrations, testicular histology, Y haplogroups and the ethnic origin of the men with deletions. PCR analysis of STS loci in the three AZF regions was used to characterize the deletions. Y haplogroup was predicted from a set of 17 Y short tandem repeats (STR) marker values. A total of nine men out of 218 infertile/subfertile men showed the presence of Y microdeletions. In eight patients the results were consistent with the presence of AZFc deletions, while in one patient a larger deletion involving both AZFb and AZFc regions was detected. In two patients, the deletion, initially diagnosed as AZFc, involved part of the distal part of the AZFb region and in one of them the deletion also extended into the region distal to the AZFc. The 3.5 Mb AZFc deletion, due to homologous recombination between b2 and b4 amplicons, was detected in six men (66.7% of all Y deletions), thus being the most common type of AZF deletion among infertile men from the Republic of Macedonia. Patients with the 3.5 Mb AZFc deletion had azoospermia or severe oligozoospermia and variable histological results [Sertoly cell only syndrome (SCOS), maturity arrest (MA) and hypospermatogenesis (HSG)]. They were of different ethnic origin (Macedonian, Albanian and Romany) and belonged to different Y haplogroups (I1b, J2, E3b and G).

Objective: The aim of this study was to evaluate the specificity and sensitivity of the real-time quantitative PCR method for fetal gender determination in early pregnancy., Methods: Blood samples were collected from 46 pregnant women prior to amniocentesis. DNA was extracted from maternal plasma using a QIAmp DNA Blood Mini Kit. DNA samples were subjected to real-time quantitative PCR amplification of SRY (as a fetus-specific marker) and beta-globin (as a marker for total plasma DNA) genes., Results: The beta-globin gene sequence was detected in all samples. The SRY gene was detected in 25 of 28 plasma samples from women with male fetuses and in none of the 18 samples from women with female fetuses (sensitivity 89.2% and specificity 100%). The fetal gender was correctly determined in 43 (93.5%) of 46 maternal plasma samples. The concentration of the beta-globin gene ranged from 161 to 25,568 genome-equivalents (GE)/mL (median 1051.1), while the concentration of the SRY gene ranged from 5 to 166 GE/mL (median 27.4). The percentage of free fetal DNA ranged from 0.1% to 46.1% (median 2.0%)., Conclusion: Amplification of fetal DNA from maternal plasma by real-time quantitative PCR is a promising method for fetal sex determination in early pregnancy. However, further studies are necessary before this procedure can be included into a clinical routine.