Yusuf Tunca

A very frequent mutation and remarkable association of R761H with M694V mutations in Turkish familial Mediterranean fever patients

Familial Mediterranean fever (FMF) is an autosomal-recessive disease. It is characterized by recurring fever, abdominal pain, and serositis. The Mediterranean fever (MEFV) gene is localized on 16p13.3 and more than 35 mutations have been described to date. There are some differences in the gene mutations of FMF in the various ethnic groups. The aim of this study is to determine the frequency of the mutations which has been reported comparatively rare, to define the most effective mutation set, and to select the most suitable DNA analysis system for Turkish FMF patients. Mutations in 330 Turkish FMF patients with typical phenotypes from various regions of Turkey were evaluated for the research purposes. These patients were analyzed for six MEFV gene mutations by the NanoChip® Molecular Genetics Workstation. The most frequent mutation was M694V, identified in 50.00% of the alleles examined; M680I followed with 14.10% and V726A—9.70%. Consequently, we determined that R761H (n = 23; 3.48%) was the most frequent rare mutations in Turkish FMF patients. Frequency of the rare mutations were R761H (3.48%), E148Q (1.36%), and M694I (1.21%). All of these mutations were in the compound heterozygote state. Our study showed that R761H mutations were higher than it has been reported in literature until now and were mainly associated with M694V. We suggest that mutation R761H should be included in the mutation scanning analysis researches or considered if the patient has M694V/? mutation especially in Turkish FMF patients. Larger serial studies need to be done to investigate the rate and coexistence of these mutations.

Hereditary TP53 Codon 292 and Somatic P16INK4A Codon 94 Mutations in a Li-Fraumeni Syndrome Family

Li-Fraumeni syndrome is an autosomal dominant disorder that is characterized by various types of cancer in childhood and adult cases. Although hereditary TP53 mutation is very rare in different human cancers, it has been frequently reported in Li-Fraumeni syndrome. On the other hand, hereditary mutations of TP57KIP2, P15INK4B, and P16INK4A, which affect the cell cycle similar to TP53, were observed in some types of cancer. In a Turkish family with the diagnosis of Li-Fraumeni syndrome, we analyzed the mutation pattern of TP53, P57KIP2, P15INK4B, and P16INK4A in the peripheral blood, and loss of heterozygosity (homo/hemizygous deletion) pattern of TP53 and P15INK4B/P16INK4A in two tumor tissues. The propositus had a seminoma, his daughter a medulloblastoma, and one of his healthy cousins, a TP53 codon 292 missense point mutation (AAA-->ATA; Lys-->Ile) in the peripheral blood cells. Tumor tissue obtained from the propositus with the seminoma revealed loss of heterozygosity in the TP53 gene. In the analyses of tumor tissues from the propositus and his daughter, a P16INK4A codon 94 missense point mutation (GCG-->GAG; Ala-->Glu) was observed with the hereditary TP53 mutation. P16INK4A codon 94 mutation observed in our family is a novel mutation in Li-Fraumeni syndrome. No other gene alteration in TP53, P57KIP2, P15INK4B, and P16INK4A was observed. Existence of the P16INK4A mutation and the hereditary TP53 mutation with or without loss of heterozygosity in the TP53 gene (seminoma/medulloblastoma) may be evidence for a common mechanism involved in tumorogenesis. The gene alterations in TP53 and P16INK4A genes may be used as tumor markers in our family.

The rate of MEFV gene mutations in hematolymphoid neoplasms

The aim of this study was to determine the rate of MEFV gene mutations, the gene responsible for familial Mediterranean fever (FMF), in patients with hematolymphoid neoplasm. The rate of the five most common MEFV gene mutations (M694V, M680I, V726A, M694I and E148Q) was determined in 46 patients with hematolymphoid neoplasm. We found a high frequency of carriers in patients with multiple myeloma (60%) and acute lymphocytic leukaemia (33.3%), whereas patients with chronic lymphocytic leukaemia (9%) and non‐Hodgkin lymphoma (5%) had a low mutation carrier rate. There is no MEFV gene mutation in patients with Hodgkin lymphoma. Furthermore, the statistically significant predominance of strong heterozygous mutations such as M694V and M680I in patients with hematolymphoid neoplasm; none had own and/or family history compatible with FMF, is interesting. In conclusion, we found a high frequency of carriers for MEFV gene in patients with multiple myeloma and acute lymphocytic leukaemia. The data of our study may provide some new insights in understanding of individual genetic differences in susceptibility to these neoplasms.

Placental chorioangioma associated with fetal cardiac complication

The mother at 27 weeks’ gestation was 25 years-old and presented with severe inguinal pain. Vital findings were normal. The hemoglobin was 11.3 g/dl (normal:14?2). Mean erythrocyte corpuscular volume and mean crythrocytc corpuscular hcmoglobin concentration were 78.5 cu microns (normal: 8725) and 30.6% (normal: 3422) respectively. Peripheral blood smear had the appearance of a microcytic anemia. Other routine hlood and urine parameters were within normal limits. Fetal ultrasonographic examination revealed hypokinesia, polyhydramnios, scalp edema, left cardiac dilatation, pericardial effusion and minimal irregularity of the fetal surface of the placenta. This status was diagnosed as ‘hydrops fetalis’. Further examinations such as hemoglobin electrophoresis, VDRL tests, TORCH tests, and tests for diabetes mellitus were normal. Coombs tests were negative. Cytogenetic studies done on material taken with chordosynthesis were reported as normal. Preterm delivery occurred within the same week. The Apgar score of the female newborn was 2. Widespread edema and minimal hepatomegaly were observed. The newborn was not anemic in appearance. Dcath occurrcd within one hour due to progressive rcspiratory distress. Crown to heel length was 46 cm, the foot length was 6.4 cm and the head circumference was 30 cm. The brain and the cerebellum were found normal. The heart was larger than normal but the left atrium was hypoplastic. The valves were normal. There was a defect, 4 mm in diameter, on the membranous segment of interatrial septum. Marked dilatation of the left ventricle was noticed. The thickness of right and left ventricular walls was 3 4 mm and &5 mm. resDectivelv. There was no tmthological finding in other organs except li)r congestion. Placenta measured 170X 160x40 mm. Fetal and maternal surfaces were normal in appearance. On serial scctions, a well defined and dark colored lesion measuring 25X25X20 Inni was found in the paracentral-subchorial region (Fig. 1 ). Histologically, a hemangiomd consisting of numerous capillary channels filled with blood was seen within a loose fibrous strorna. No increased cellularity, mitotic figures or degenerative changes were present.

Biomedical visual data analysis to build an intelligent diagnostic decision support system in medical genetics

BACKGROUND In general, medical geneticists aim to pre-diagnose underlying syndromes based on facial features before performing cytological or molecular analyses where a genotype-phenotype interrelation is possible. However, determining correct genotype-phenotype interrelationships among many syndromes is tedious and labor-intensive, especially for extremely rare syndromes. Thus, a computer-aided system for pre-diagnosis can facilitate effective and efficient decision support, particularly when few similar cases are available, or in remote rural districts where diagnostic knowledge of syndromes is not readily available. METHODS The proposed methodology, visual diagnostic decision support system (visual diagnostic DSS), employs machine learning (ML) algorithms and digital image processing techniques in a hybrid approach for automated diagnosis in medical genetics. This approach uses facial features in reference images of disorders to identify visual genotype-phenotype interrelationships. Our statistical method describes facial image data as principal component features and diagnoses syndromes using these features. RESULTS The proposed system was trained using a real dataset of previously published face images of subjects with syndromes, which provided accurate diagnostic information. The method was tested using a leave-one-out cross-validation scheme with 15 different syndromes, each of comprised 5-9 cases, i.e., 92 cases in total. An accuracy rate of 83% was achieved using this automated diagnosis technique, which was statistically significant (p<0.01). Furthermore, the sensitivity and specificity values were 0.857 and 0.870, respectively. CONCLUSION Our results show that the accurate classification of syndromes is feasible using ML techniques. Thus, a large number of syndromes with characteristic facial anomaly patterns could be diagnosed with similar diagnostic DSSs to that described in the present study, i.e., visual diagnostic DSS, thereby demonstrating the benefits of using hybrid image processing and ML-based computer-aided diagnostics for identifying facial phenotypes.

High frequency of MEFV gene mutations in patients with myeloid neoplasm

We aimed to investigate the rate of MEFV, the gene mutated in familial Mediterranean fever, mutations in patients with myeloid neoplasm and to determine if known mutations of MEFV cause a tendency for myeloid neoplasms. The frequency of the five most common MEFV gene mutations (M694V, M680I, V726A, E148Q and M694I) was determined in 26 patients with myeloid neoplasm. We identified 1 homozygous (E148Q/E148Q), 1 compound heterozygous (M694V/E148Q) and 5 heterozygous MEFV gene mutations; none had their own and/or family history compatible with familial Mediterranean fever. The mean overall mutation rate was 0.269. We found a high frequency of carriers in patients with myelodysplastic syndrome (66.6%), polycythemia vera (33.3%) and acute myeloid leukemia (28.6%). However, there was no MEFV gene mutation in patients with chronic myeloid leukemia. In conclusion, this study reports for the first time a possibly high prevalence of MEFV gene mutations in patients with myeloid neoplasm, especially myelodysplastic syndrome, polycythemia vera and acute myeloid leukemia. Our findings could open new perspectives for MEFV gene mutations in myeloid neoplasms and its association with tumor promotion. Further research is needed to determine the actual role of MEFV gene mutations in these malignancies.

New heritable fragile site at 15q13 in both members of a nonconsanguineous couple

The detection of a fragile site in a patient often causes concerns due to its potential significance and the necessity to be followed‐up properly with genetic counseling. Here we present a new heritable fragile site at 15q13, which was spontaneously expressed at a high frequency in lymphocytes culture of both members of a nonconsanguineous couple with recurrent abortions. The fragile site was not detected in the parents of the female, while the male had inherited it from his father. The fragile site was seen ≥85% of cells in all the carriers. To the best of our knowledge, the presence of this fragile site is being described for the first time under different culture conditions. While it looks like the fragile site is harmless in all carriers, having heterozygosity in the couple may lead to homozygous offspring that could result in fetal loss.

Existe uma relação entre a artrite gotosa e as mutações genéticas da febre familiar do Mediterrâneo

OBJECTIVE Gouty arthritis and familial Mediterranean fever (FMF) share some clinical and pathological features such as being classified as auto inflammatory disease, association with inflammasome, short-lived intermittent arthritis, and good response to colchicine and anti-interleukin-1 treatments. As Mediterranean fever (MEFV) gene is the causative factor of FMF, we aimed to investigate the prevalence of MEFV gene mutations and their effect on disease manifestations in Turkish gouty arthritis patients. METHODS Ninety-seven patients diagnosed with primary gouty arthritis (93M and 4 F, 54 [37-84] years) and 100 healthy controls (94M and 6 F, 57 [37-86] years) included in the study. All subjects were genotyped for the MEFV variations. Number of gout attacks, diuretic use, and history of nephrolithiasis and presence of tophus were also recorded. RESULTS The carriage rate of MEFV mutations for patients and controls were 22.7% (n=22) and 24% (n=24) respectively. The comparison of the patient and control groups yielded no significant difference in terms of the MEFV mutations carriage rate (p=0.87). The allelic frequencies of the MEFV mutations in patients were 11.9% (n=23) and 14% (n=28) in controls (p=0.55). The presence of MEFV variants did not show any association with clinical features of gouty arthritis. The subgroup analysis of patients revealed that gouty arthritis patients with mutations had similar frequencies of tophus, history of nephrolithiasis and podogra compared to the ones without mutations (p>0.05). CONCLUSIONS This study does not provide support for a major role of MEFV mutations in Turkish gouty arthritis patients.

The presence of MEFV gene mutations in patients with primary osteoarthritis who require surgery

Background/Aims Chronic arthritis of familial Mediterranean fever (FMF) involves weight-bearing joints and can occur in patients without a history of acute attack. Our aim was to investigate a possible causal relationship between FMF and osteoarthritis in a population in which FMF is quite common. Methods Patients with late stage primary osteoarthritis were enrolled, and five MEFV gene mutations were investigated. The frequency of MEFV gene mutations was compared among patients with osteoarthritis and a previous healthy group from our center. Results One hundred patients with primary osteoarthritis and 100 healthy controls were studied. The frequency of MEFV gene mutations was significantly lower in the osteoarthritis group (9% vs. 19%). M694V was the most frequent mutation (5%) in the osteoarthritis group, whereas in the control group, E148Q was the most common (16%). In subgroup analyses, the mutation frequency of patients with hip osteoarthritis was not different from that of patients with knee osteoarthritis and controls (7.1%, 9.7%, and 19%, respectively). There were no differences among the three groups with respect to MEFV gene mutations other than E148Q (8.1% vs. 3.6%). E148Q was significantly lower in the osteoarthritis group than in the controls (16% vs. 1%), although the mutations did not differ between patients with knee osteoarthritis and controls. Conclusions In a population with a high prevalence of MEFV gene mutations, we did not find an increased mutation rate in patients with primary osteoarthritis. Furthermore, we found that some mutations were significantly less frequent in patients with osteoarthritis. Although the number of patients studied was insufficient to claim that E148Q gene mutation protects against osteoarthritis, the potential of this gene merits further investigation.

Establishment of a Diagnostic Decision Support System in Genetic Dysmorphology

In the clinical diagnosis of facial dysmorphology, geneticists attempt to identify the underlying syndromes by associating facial features before cyto or molecular techniques are explored. Specifying genotype-phenotype correlations correctly among many syndromes is labor intensive especially for very rare diseases. The use of a computer based prediagnosis system can offer effective decision support particularly when only very few previous examples exist or in a remote environment where expert knowledge is not readily accessible. In this work we develop and demonstrate that accurate classification of dysmorphic faces is feasible by image processing of two dimensional face images. We test the proposed system on real patient image data by constructing a dataset of dysmorphic faces published in scholarly journals, hence having accurate diagnostic information about the syndrome. Our statistical methodology represents facial image data in terms of principal component analysis (PCA) and a leave one out evaluation scheme to quantify accuracy. The methodology has been tested with 15 syndromes including 75 cases, 5 examples per syndrome. A diagnosis success rate of 79% has been established. It can be concluded that a great number of syndromes indicating a characteristic pattern of facial anomalies can be typically diagnosed by employing computer-assisted machine learning algorithms since a face develops under the influence of many genes, particularly the genes causing syndromes.