Tissue and plasma proteomic profiling indicates AHSG as a potential biomarker for ascending thoracic aortic aneurysms.

BACKGROUND: Thoracic Aortic Aneurysms (TAAs) develop asymptomatically and are characterized by dilatation of the aorta. This is considered a life-threatening vascular disorder due to the risk of aortic dissection and rupture. There is an urgent need to identify blood-borne biomarkers for the early detection of TAA. The goal of the present study was to identify potential protein biomarkers associated with TAAs, using proteomic analysis of aortic tissue and plasma samples. METHODS: Extracted proteins from 14 aneurysmal and 12 non-aneurysmal thoracic aortic tissue specimens as well as plasma samples from six TAA patients collected pre-and postoperatively and six healthy controls (HC), were analyzed by liquid chromatography-tandem mass spectrometry. Proteomic data were further processed and following filtering criteria, one protein was selected for verification and validation in a larger cohort of patients and controls using a targeted quantitative proteomic approach and enzyme-linked immunosorbent assay, respectively. RESULTS: A total of 1593 and 363 differentially expressed proteins were identified in tissue and plasma samples, respectively. Pathway enrichment analysis on the differentially expressed proteins revealed a number of dysregulated molecular pathways that might be implicated in aneurysm pathology including complement and coagulation cascades, focal adhesion, and extracellular matrix receptor interaction pathways. Alpha-2-HS glycoprotein (AHSG) was selected for further verification in 36 TAA and 21 HC plasma samples using targeted quantitative proteomic approach. The results showed a significantly decreased concentration of AHSG (p = 0.0002) in the preoperative plasma samples compared with HC samples. Further analyses using a larger validation dataset revealed that AHSG protein levels were significantly lower (p = 0.03) compared with HC. Logistic regression analysis on the validation dataset revealed males, advanced age, hypertension and hyperlipidaemia as significant risk factors for TAA. CONCLUSION: AHSG concentrations distinguish plasma samples derived from TAA patients and controls. The findings of this study suggest that AHSG may be a potential biomarker for TAA that could lead to better diagnostic capabilities.

Novel variants in the ACTA2 and MYH11 genes in a Cypriot family with thoracic aortic aneurysms: a case report.

BACKGROUND: Thoracic aortic aneurysm (TAA) and/or thoracic aortic aneurysm and dissection (TAAD) is characterized by a considerable risk of morbidity and mortality of affected individuals. It is inherited in an autosomal dominant pattern and the 20% of patients with non-syndromic TAA have a positive family history. To date, the genetic basis of Cypriot patients with TAA has not been investigated. The purpose of this case report is to determine underlying genetic cause in this Cypriot family with TAA. CASE PRESENTATION: In this report we present a patient with hyper-acute onset chest and back pain diagnosed with Type A Aortic Dissection with severe aortic valve regurgitation, who underwent emergency aortic surgery and Bentall procedure. Further investigation of the patient's family was undertaken where both parents and an additional child were also found to be affected. A targeted sequencing panel including genes with known association to TAA was used to identify causative mutations in the index patient. Massively Parallel Sequencing results identified a frameshift deletion c.363_367del GAGTC, p.Met121Ilefs*5 in the ACTA2 gene and a non-synonymous variant c.3234C > G, p.Ile1078Met in the MYH11 gene. The presence or absence of these variants in the index patient and other family members was verified by Sanger sequencing. To our knowledge, this is the first report of a Cypriot family case diagnosed with TAA presented by two novel variants one in the ACTA2 and the other in the MYH11 genes. CONCLUSIONS: We describe two novel variants in a Cypriot family with TAA that are potentially pathogenic, highlighting the importance of molecular genetic evaluation in families with TAA. These results may prove useful for screening purposes in Cypriot patients with non-syndromic familial TAA facilitating early identification of atrisk family members and direct intervention.

MicroRNAs as possible biomarkers for screening of aortic aneurysms: a systematic review and validation study.

CONTEXT: There is an urgent need to identify non-invasive biomarkers for the early detection of aortic aneurysms, preceding a fatal event. The potential role for MicroRNAs (miRNAs) as diagnostic markers for aortic aneurysms was investigated through the present systematic review. OBJECTIVE: To perform a comprehensive review on published studies examining the association of miRNAs with aortic aneurysms and further validate these results with plasma samples collected from thoracic aortic aneurysm (TAA) patients. METHODS: The literature search was performed via numerous databases and articles were only included if they fulfilled the predefined eligibility criteria. The miRNAs reported three times or more with expression consistency were validated using plasma samples from TAA patients collected before and following surgery. RESULTS: Twenty-four articles were selected from the literature search and 11 miRNAs were chosen for validation using our samples. The miRNAs which were further validated were found to follow the trend in the regulation pattern as with the majority of the published data. MiRNA hsa-miR-193a-5p was found to be significantly down-regulated in the plasma samples collected before the aneurysmal removal when compared with postsurgical serum samples. CONCLUSIONS: Numerous miRNAs have been associated with aortic aneurysms, and specifically hsa-miR-193a-5p and hsa-miR-30b-5p; therefore they warrant further investigation as potential biomarkers. Registration: The protocol of the review was registered in Prospero Databases (ID: CRD42016039953).

Sex-specific age association with primary DNA transfer.

Practicing forensic scientists who are called to provide expert witness testimony are often asked to explain both the presence and the absence of DNA on objects that have been handled by perpetrators with bare hands. Unwashed hands, depending on what they have come in contact with previously, may become the vehicle of both primary and secondary transfer of DNA. In this study, we investigated the propensity of primary and secondary transfer of DNA from unwashed bare hands of 128 individuals onto plastic tubes. Our experiments, carried out in triplicate, have shown that DNA was not detected on all the touched tubes, secondary transfer of DNA, through unwashed hands, was small, and in the majority of cases primary DNA transfer could be distinguished from secondary DNA transfer. A statistically significant association was demonstrated between percent DNA profile deposited on plastic tubes, through unwashed hands, and the age of male individuals.

Fatal gunshot trauma of a child: A case from colonial Cyprus.

Forensic science has made some significant contributions to the investigation of human rights abuses related to armed conflicts, especially in the last 40 years. Some investigations are aimed at the collection of evidence in order to prosecute those responsible, while others are humanitarian in nature. This paper presents the multidisciplinary effort to recover and identify the remains of a 7-year-old child who was shot by British colonial forces in Cyprus in 1956. An investigation led to the discovery of the burial site, and archaeological methods were used to recover the remains. The anthropological examination provided information about the age of the child, as well as the nature of the skeletal trauma present. DNA results confirmed the identity of the victim, and the remains were released to the surviving family members for burial.

Deciphering the maternal ancestral lineage of Greek Cypriots, Armenian Cypriots and Maronite Cypriots.

Cyprus was conquered from several populations because of its special geographical location. In this study, 406 unrelated Cypriot samples were tested based on their mitochondrial DNA. In more detail, 185 were Greek Cypriots, 114 Armenian Cypriots and 107 Maronite Cypriots. This is the first time where the mitochondrial DNA of Greek Cypriots, Armenian Cypriots and Maronite Cypriots is compared with the aim of characterizing the maternal ancestry of Cypriots. The control region of the mtDNA is the most informative in terms of studying maternal ancestry and consists of three hypervariable regions (HVS-I, HVS-II, HVS-III). The hypervariable regions can provide important information regarding the maternal ancestor of the tested samples. The entire control region of the mtDNA was used to determine the mitotypes and subsequently the haplogroups of all the Cypriot DNA samples. Based on the aforementioned analyses, Greek Cypriots were found to be genetically closer to Armenian Cypriots, while Greek Cypriots and Armenian Cypriots showed moderate genetic differentiation with Maronite Cypriots. The most prevalent haplogroups among Cypriots were haplogroups H and U, while R0 is common but in different frequencies for Greek Cypriots, Armenian Cypriots and Maronite Cypriots. It is proposed that the maternal ancestor may have originated during the Neolithic period and/or the Bronze age.

Correction: Comparative Y-chromosome analysis among Cypriots in the context of historical events and migrations.

[This corrects the article DOI: 10.1371/journal.pone.0255140.].

The Cyprus Institute of Neurology and Genetics, an emerging paradigm of a gender egalitarian organisation.

Females are underrepresented in the science, technology, engineering, mathematics and medicine (STEMM) disciplines globally and although progress has been made, the gender gap persists. Our aim was to explore gender parity in the context of gender representation and internal collaboration at the Cyprus Institute of Neurology and Genetics (CING), a leading national biomedical organisation accredited as an equal opportunity employer. Towards this aim we (1) explored trends in gender parity within the different departments, positions and qualifications and in student representation in the CING's postgraduate school and, (2) investigated the degree of collaboration between male and female researchers within the Institute and the degree of influence within its co-authorship network. We recorded an over-representation of females both in the CING employees and the postgraduate students. The observed female over-representation in pooled CING employees was consistent with a similar over-representation in less senior positions and was contrasted with an observed male over-representation in only one middle rank and culminated in gender equality in the top rank in employee hierarchy. In terms of collaboration, both males and females tended to collaborate with each other without any significant preference to either inter-group or intra-group collaboration. Further comparison of the two groups with respect to their influence in the network in terms of occupying the positions of highest centrality scores, indicated that both gender and seniority level (head vs non-head) were significant in shaping the authors' influence, with no significant difference in those belonging in the same seniority level with respect to their gender. To conclude, our study has validated the formal recognition of the CING's policies and procedures pertinent to its egalitarian culture through the majority of the metrics of gender equality assessed in this study and has provided an extendable paradigm for evaluating gender parity in academic organizations.

Comparative Y-chromosome analysis among Cypriots in the context of historical events and migrations.

Y-chromosome analysis provides valuable information regarding the migration patterns of male ancestors, ranging from the Paleolithic age to the modern humans. STR and SNP genotyping analysis provides data regarding the genetic and geographical ancestry of the populations studied. This study focused on the analysis of the Y-chromosome in Maronite Cypriots and Armenian Cypriots, who came to the island as a result of different historical events. The aim was to provide information on the paternal genetic ancestry of Maronites and Armenians of Cyprus and investigate any affinity with the Greek Cypriots and Turkish Cypriots of the island. Since there is limited information in the current literature, we proceeded and used 23 Y-chromosome STRs and 28 Y-chromosome SNPs to genotype 57 Maronite Cypriots and 56 Armenian Cypriots, which were then compared to data from 344 Greek Cypriots and 380 Turkish Cypriots. All samples were assigned to eight major Y-haplogroups but the most frequent haplogroup among all Cypriots is haplogroup J in the major subclade J2a-L559. The calculated pairwise genetic distances between the populations show that Armenian Cypriots are genetically closer to Greek and Turkish Cypriots compared to Maronite Cypriots. Median Joining Network analysis in 17 Y-STR haplotypes of all Cypriots assigned to J2a-L559, revealed that Cypriots share a common paternal ancestor, prior to the migration of the Armenians and Maronites to Cyprus, estimated in the Late Bronze Age and Early Iron Age.

Genetic variation in genes interacting with BRCA1/2 and risk of breast cancer in the Cypriot population.

Inability to correctly repair DNA damage is known to play a role in the development of breast cancer. Single nucleotide polymorphisms (SNPs) of DNA repair genes have been identified, which modify the DNA repair capacity, which in turn may affect the risk of developing breast cancer. To assess whether alterations in DNA repair genes contribute to breast cancer, we genotyped 62 SNPs in 29 genes in 1,109 Cypriot women with breast cancer and 1,177 age-matched healthy controls. Five SNPs were associated with breast cancer. SNPs rs13312840 and rs769416 in the NBS1 gene were associated with a decrease in breast cancer risk (OR TT vs. TC/CC = 0.58; 95% CI, 0.37-0.92; P = 0.019 and OR GG vs. GT/TT = 0.23, 95% CI 0.06-0.85, P = 0.017, respectively). The variant allele of MRE11A rs556477 was also associated with a reduced risk of developing the disease (OR AA vs. AG/GG = 0.76; 95% CI, 0.64-0.91; P = 0.0022). MUS81 rs545500 and PBOV1 rs6927706 SNPs were associated with an increased risk of developing breast cancer (OR GG vs. GC/CC = 1.21, 95% CI, 1.02-1.45; P = 0.031; OR AA vs. AG/GG = 1.53, 95% CI, 1.07-2.18; P = 0.019, respectively). Finally, haplotype-based tests identified significant associations between specific haplotypes in MRE11A and NBS1 genes and breast cancer risk. Further large-scale studies are needed to confirm these results.

MicroRNAs in ascending thoracic aortic aneurysms.

Thoracic Aortic Aneurysm (TAA) is characterized by the dilation of the aorta and is fatal if not diagnosed and treated appropriately. The underlying genetic mechanisms have not been completely delineated, so better knowledge of the physiopathology of TAAs is needed to improve detection and therapy. MicroRNAs (miRNAs) regulate gene expression post-transcriptionally and are known to be involved in cardiovascular diseases (CVDs). The current study aimed to identify miRNAs that can be used as possible biomarkers for the early diagnosis of patients with ascending TAAs (ATAAs). MiRNA expression was profiled by NanoString nCounter technology using 12 samples including tissue and pre- and post-surgical plasma from ATAA patients. Four miRNAs were selected and further validated by real time polymerase chain reaction (RT-PCR) in 22 plasma samples from which three miRNAs (hsa-miR140-5p, hsa-miR-191-5p and hsa-miR-214-3p) showed significant expression level differences between the two types of plasma samples. Further analyses of the corresponding predicted target genes by these miRNAs, revealed two genes (Myotubularin-related protein 4 (MTMR4) and Phosphatase 1 catalytic subunit ß (PPP1CB)) whose expression was inversely correlated with the expression of their respective miRNAs. Overall, in this pilot study, we identified three miRNAs that might serve as potential biomarkers and therapeutic targets in ATAA.

Identification of novel splice mutation in SMAD3 in two Cypriot families with nonsyndromic thoracic aortic aneurysm. Two case reports.

BACKGROUND: Thoracic aortic aneurysm and dissection (TAA/D) represents a potentially lethal disease group characterized by an increased risk of dissection or rupture. Only a small percentage (approximately 30%) of individuals with nonsyndromic familial TAA/D have a pathogenic variant in one of the genes that have been found to be associated with the disease. METHODS: A targeted sequencing panel and direct sequencing approach were used to identify causative mutations in the index patients and other family members. RESULTS: In this study we report two apparently unrelated Cypriot families with nonsyndromic familial TAA/D. The proband A is a female patient diagnosed with TAA/D and intracranial aneurysm and opted for an elective intervention. The proband B is a male patient who was diagnosed with TAA/D and underwent cardiac surgery. Sequencing analysis identified a novel splice site variant (c.871+1G>A) in SMAD3 which is shown to be associated with the disease. Analysis of mRNA from the patient's tissue confirmed aberrant splicing and exon 6 skipping. CONCLUSION: Our findings expand the mutation spectrum of variants that have been shown to be associated with nonsyndromic familial TAA/D. This study demonstrates the importance of a comprehensive clinical and genetic evaluation aiming at early diagnosis and intervention.

Effect of paraoxonase 1 polymorphisms on the response of lipids and lipoprotein-associated enzymes to treatment with fluvastatin.

BACKGROUND: Decreased paraoxonase 1 (PON1) and increased total serum lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) activities are suggested to be risk factors for vascular disease. Common PON1 genetic polymorphisms (Q192R and L55M) significantly affect PON1 activity and may also influence high-density lipoprotein (HDL)-associated Lp-PLA(2) activity. However, little is known about the possible effect of PON1 common genetic polymorphisms on the response of lipids as well as PON1 and Lp-PLA(2) activities to treatment with statins. METHODS: Two hundred two hypercholesterolemic patients were treated with fluvastatin 40 mg/day. Fasting serum lipids, Q192R and L55M PON1 polymorphisms as well as PON1 and Lp-PLA(2) (total serum and HDL-associated) activities were determined before and after 6 months of treatment. RESULTS: Fluvastatin treatment did not affect HDL-cholesterol or apolipoprotein (apo) AI but resulted in significant decreases in total cholesterol, triglycerides, low-density lipoprotein-cholesterol, apo B and apo E, as well as total serum Lp-PLA(2) activity. In contrast, PON1 activity significantly increased. None of these changes was influenced by Q192R or L55M PON1 polymorphisms. Overall, HDL-Lp-PLA(2) did not change but L55M polymorphism significantly influenced its response to fluvastatin. Specifically, LL homozygotes experienced a significant increase, while M carriers (LM or MM) experienced a non-significant decrease in HDL-Lp-PLA(2) activity (p = 0.030 between groups). CONCLUSIONS: Q192R and L55M PON1 polymorphisms did not affect the response of lipids, PON1 and total serum Lp-PLA(2) to treatment with a statin. However, L55M PON1 polymorphism significantly modulated the response of HDL-Lp-PLA(2). It should be noted that this is an association study and therefore provides no proof but only indication that PON1 may also exert Lp-PLA(2) activity in HDL.

Y-chromosomal analysis of Greek Cypriots reveals a primarily common pre-Ottoman paternal ancestry with Turkish Cypriots.

Genetics can provide invaluable information on the ancestry of the current inhabitants of Cyprus. A Y-chromosome analysis was performed to (i) determine paternal ancestry among the Greek Cypriot (GCy) community in the context of the Central and Eastern Mediterranean and the Near East; and (ii) identify genetic similarities and differences between Greek Cypriots (GCy) and Turkish Cypriots (TCy). Our haplotype-based analysis has revealed that GCy and TCy patrilineages derive primarily from a single gene pool and show very close genetic affinity (low genetic differentiation) to Calabrian Italian and Lebanese patrilineages. In terms of more recent (past millennium) ancestry, as indicated by Y-haplotype sharing, GCy and TCy share much more haplotypes between them than with any surrounding population (7-8% of total haplotypes shared), while TCy also share around 3% of haplotypes with mainland Turks, and to a lesser extent with North Africans. In terms of Y-haplogroup frequencies, again GCy and TCy show very similar distributions, with the predominant haplogroups in both being J2a-M410, E-M78, and G2-P287. Overall, GCy also have a similar Y-haplogroup distribution to non-Turkic Anatolian and Southwest Caucasian populations, as well as Cretan Greeks. TCy show a slight shift towards Turkish populations, due to the presence of Eastern Eurasian (some of which of possible Ottoman origin) Y-haplogroups. Overall, the Y-chromosome analysis performed, using both Y-STR haplotype and binary Y-haplogroup data puts Cypriot in the middle of a genetic continuum stretching from the Levant to Southeast Europe and reveals that despite some differences in haplotype sharing and haplogroup structure, Greek Cypriots and Turkish Cypriots share primarily a common pre-Ottoman paternal ancestry.

The cypriot and Iranian National Mutation Frequency Databases.

The National Mutation Frequency Databases are continuously updated mutation depositories, which contain extensive information over the described genetic heterogeneity of an ethnic group or population. Here, we report the construction of the Cypriot (http://www.goldenhelix.org/cypriot) and Iranian National Mutation Frequency Databases (http://www.goldenhelix.org/iranian), both derived from an academic effort to provide high quality and up-to-date information on the underlying genetic heterogeneity of inherited disorders in the Cypriot and Iranian populations, respectively. Both databases have been built and maintained online using ETHNOS platform, a specialized software, which provides the means for national mutation database construction and curation. Each database contains brief summaries of the various genetic disorders studied for each population, and an easy-to-use query interface provides, both to specialist as well as to non-specialist users (i.e. patients and their families), instant access to the list and frequencies of the different mutations responsible for the inherited disorders in these populations. Furthermore, numerous links to the respective Online Mendelian Inheritance in Man (OMIM) entries and, when available, to the locus-specific databases fruitfully integrate the databases content into a single Web site. Both databases can serve as valuable online tools for molecular genetic testing of inherited disorders in these populations and could potentially motivate further investigations of yet unknown genetic diseases in the Cypriot and Iranian populations.

The effect of apolipoprotein E polymorphism on the response to lipid-lowering treatment with atorvastatin or fenofibrate.

Although the effect of apolipoprotein E gene polymorphism on the response to treatment with statins has been studied, the results are conflicting. Moreover, little is known about the possible effect of apolipoprotein E alleles on the response to treatment with fibrates. The purpose of this study was to evaluate the effect of apolipoprotein E polymorphism on lipid-lowering response to treatment with atorvastatin and fenofibrate in patients with different types of dyslipidemia. The study population included 136 patients with heterozygous familial hypercholesterolemia (type IIA dyslipidemia) treated with atorvastatin (20 mg/day) and 136 patients with either primary hypertriglyceridemia (type IV dyslipidemia) or mixed hyperlipidemia (type IIB dyslipidemia) treated with micronized fenofibrate (200 mg/day). Overall, no significant associations were detected between apolipoprotein E genotype and response to treatment with atorvastatin. In patients treated with fenofibrate, significant associations were noted between apolipoprotein E genotype and changes in apolipoprotein B, apolipoprotein E and triglyceride levels. Specifically, in apolipoprotein E2, apolipoprotein E3, and apolipoprotein E4 individuals, apolipoprotein B reductions were 22%, 17%, and 8%, respectively (P = .003); apolipoprotein E reductions were 45%, 20%, and 15%, respectively (P = .006); whereas triglyceride reductions reached 53%, 36%, and 33%, respectively (P = .033). In conclusion, apolipoprotein E genotype had no significant effect on the response to treatment with atorvastatin in patients with heterozygous familial hypercholesterolemia, but in patients with primary hypertriglyceridemia or mixed hyperlipidemia, there was a clear association between apolipoprotein E genotype and response to treatment with fenofibrate.

Plasma lipoprotein(a) levels and LDL-cholesterol lowering response to statin therapy in patients with heterozygous familial hypercholesterolemia.

Familial hypercholesterolemia (FH) is characterised by elevated plasma LDL-cholesterol levels and premature ischemic heart disease. Statin therapy is mandatory in order to prevent atherosclerosis in patients with heterozygous FH. Both genetic and environmental factors affect the statin-induced LDL-cholesterol lowering effect in patients with heterozygous FH. Recently published data suggest that plasma lipoprotein(a) levels may affect the efficacy of statin therapy in patients with nephrotic syndrome. However, no data are available concerning the effect of lipoprotein(a) levels on the efficacy of statin therapy in patients with heterozygous FH. This report demonstrates negative correlation between plasma lipoprotein(a) levels and the LDL-cholesterol lowering effect of statin therapy in 49 patients with heterozygous FH.

Allele distribution of 15 STR loci used for human identity purposes in the Greek Cypriot population of the island of Cyprus.

Allele frequencies for 15 STRs (D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, THO1, Penta E, D16S539, CSF1PO, Penta D and TPOX) in the PowerPlex-16 System (Promega Corporation) were derived from a sample of 1475 unrelated Greek Cypriot individuals from the island of Cyprus.

Effect of apolipoprotein E polymorphism on serum uric acid levels in healthy subjects.

BACKGROUND: We have previously shown that apolipoprotein E (apo E-) polymorphism may affect serum creatinine concentration and predicted glomerular filtration rate in healthy individuals. On the other hand, there are limited data regarding the possible influence of apo E- polymorphism on serum uric acid (SUA) levels. METHODS: Two hundred ninety (148 male, 142 female) apparently healthy white individuals were studied. apo E- genotypes, serum lipid parameters including apolipoproteins, insulin resistance using the homeostasis model assessment (HOMA) as a marker, serum and urine creatinine levels, and serum and urine uric acid concentration were determined in all participants. RESULTS: The apo E-2 allele was associated with lower serum levels of total cholesterol, higher levels of triglycerides and apo E-, and increased serum creatinine concentration compared with the apo E-3 and apo E-4 alleles in our population. Furthermore, the apo E-2 allele was associated with higher SUA levels (321.3+/-101.1 micrmol/L [5.4+/-1.7 mg/dL]) compared with the apo E-3 allele (261.8+/-89.2 micromol/L [4.4+/-1.5 mg/dL]; p= .012) and the apo E-4 allele (243.9+/-65.4 micromol/L [4.1+/-1.1 mg/dL]; p= .010), whereas the apo E-2 allele was associated with a nonsignificantdecrease in the fractional renal excretion of uric acid (FEUA) compared with the apo E-3 and apo E-4 alleles (7.9+/-2.2% vs 8.7+/-4.2% vs 8.9+/-5.1%, respectively; p = .53). These observations remained statistically significant when the effect of apo E- polymorphism on SUA levels was adjusted for gender, age, systolic and diastolic blood pressure, body mass index, serum creatinine, and triglyceride and apo E- levels, as well as for HOMA index and FEUA. CONCLUSIONS: Our data provide evidence, for the first time, that the apo E-2 allele is independently associated with increased SUA levels in healthy individuals.

Apolipoprotein E genotype in matched men and women with coronary heart disease.

Apolipoprotein E (apo E) plays an important role in lipid metabolism and its polymorphism may be a risk determinant of coronary heart disease (CHD). Since evidence suggested a gender-specific effect of apo E polymorphism, we studied the influence of gender-specific interaction of the polymorphism on CHD. From a total of 463 Greek Caucasians (314 men and 149 postmenopausal women) with angiographically documented CHD, we selected 79 women (68+/- 9 yr old) and 79 men (66+/- 9 yr old) who were matched for clinical characteristics. Apo E genotyping was performed by PCR and RFLP analysis. Biochemical parameters were also measured. The results were as follows: the E3/3 genotype occurred in 78.5% of the patients, followed by E3/4, E2/3, E2/4, and E4/4 genotypes, which occurred in 9.5%, 9.5%, 1.9%, and 0.6% of the patients, respectively. No significant differences were observed in the apo E allele or apo E genotype distributions between the matched Greek men and women with CHD. The E3/3 men patients were more frequently part of a family with a history of CHD, compared to women (p=0.035).