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Inverted 8p duplication deletions are recurrent chromosomal rearrangements that most often arise through non-allelic homologous recombination (NAHR) during maternal meiosis between segmental duplications made up of the olfactory receptor (OR) gene clusters. The presence of a paracentric inversion polymorphism in 8p23.1, found in approximately 26% of European population, may trigger meiotic misalignment and NAHR between the OR gene repeats. We report clinical, cytogenetic, and molecular findings in a 4 year 8 month-old female with concomitant inverted duplication and terminal deletion of chromosome 8p. The girl, the first child of unrelated parents, was born at term, by normal delivery, after an uneventful pregnancy. Clinical examination revealed dysmorphic features, pectus excavatum, hypertonia, severe developmental delay. Brain ultrasound and MRI showed agenesis of the corpus callosum without other abnormalities. Conventional cytogenetic analysis identified additional material on chromosome 8 at band p21. SNP array analysis further characterized the abnormality as a duplication of about 31.3 Mb, from 8p23.1 to 8p11.1, and additionally revealed a terminal deletion of about 6.8 Mb, from 8p23.3 to 8p23.1. Genomic microarray also identified a region of disomy between deletion and duplication. Chromosome analysis of both parents revealed normal results. Based on clinical examination, conventional cytogenetics and SNP array, we established the diagnosis of inverted duplication deletion of 8p. SNP array analysis precisely defined the breakpoints of rearrangement and, by identifying a region of disomy between the duplication and deletion, indicated that NAHR between segmental duplications was the most likely mechanism for this type of abnormality.

Unlabelled: Trisomy X (47,XXX) is a gonosomal aneuploidy characterized by the presence of an extra X chromosome in a female person. Usually the diagnosis is established made postnatally by chromosome analysis in patients with suggestive clinical signs. Clinical signs vary by age. In prepubertal patients have a growth retardation associated with uncharacteristic facial dysmorphism, mild mental retardation with behavioral disorders, plus clinical signs of ovarian dysgenesis, postpubertal., Aim: We analyzed retrospectively the genotype - phenotype correlations for a selected group of 36 patients diagnosed with trisomy X (homogeneous or mosaic) by cytogenetic methods (X chromatin and karyotype)., Material and Methods: Analysis of the clinical data of 36 patients diagnosed with trisomy X and correlation with the results of X chromatin and karyotype., Results: Clinical signs detected in patients with homogeneous trisomy X 47,XXX (22.22%), mosaic 46,XX/47,XXX (16.66%) or 47,XXX/48,XXXX (5.55%) were prepubertal, growth retardation associated with dysmorphic facial (upslanted palpebral fissure, epichantus, thin lips) and postpubertal, signs of ovarian dysgenesis (secondary amenorrhea, early menopause). The phenotype of patients with different gonosomal mosaic corresponding to Turner syndrome, incorporating a cell line with trisomy X (55.55%) was variable, correlated with the type of chromosomal abnormalities detected., Conclusions: The results of our study are similar to those obtained in other studies and emphasizes that phenotypic variability of patients with trisomy X feature makes it difficult to genotype - phenotype correlations.

Unlabelled: Patau syndrome has an incidence of 1/10.000-20.000, the clinical diagnosis being suggested by the triad cleft lip and palate, microphthalmia/anophthalmia and postaxial polydactyly. Most frequent cytogenetic abnormality is free and homogeneous trisomy 13 (80.0%), rarely being detected trisomy mosaics or Robertsonian translocations. The objective of the study was to identify phenotypic features of trisomy 13., Material and Methods: The retrospective study was conducted on a trial group of 14 cases diagnosed cytogenetically with trisomy 13 between January 2000 and December 2012 at lasi Medical Genetics Centre., Results: Of the 14 cases, 3 were evaluated pathologically (two aborted foetuses and one stillborn), 8 cases were detected in the neonatal period, and 3 in infancy. Clinical diagnosis was supported by the identification of a model of abnormal development, mainly characterized by: maxillary cleft (lip and palate--5 cases; lip--1 case), ocular abnormalities (microphthalmia/anophthalmia--7 cases; cyclopia--1 case), postaxial polydactyly (7 cases), scalp defects (6 cases), congenital heart anomalies (10 cases, 6 patients with atrial septal defect), complete holoprosencephaly (4 cases), ear abnormalities (11 cases), broad nasal root (10 cases). An important issue in confirming the phenotypic variability of Patau syndrome is that the classic clinical triad was identified only in one case., Conclusions: Patau syndrome is a disease with variable expression and is characterized by a pattern of abnormal prenatal development characterized by facial dysmorphia, polydactyly and severe birth defects (heart, brain) that generate an increased in utero and perinatal mortality.

Aim: the purpose of the present study was to determine the relationship between the Clopidogrel genetic response (based on laboratory specific tests) and the worse evolution of the patients with acute coronary syndromes., Material and Methods: The study included 80 patients (11 females and 69 males), aged between 45 - 85 years, admitted in the 1st Department of Cardiology, between January June 2012, diagnosed with acute coronary syndromes (especially unstable angina). All the patients received Clopidogrel as antiplatelet agent, in some cases associated with aspirin. The diagnosis of acute coronary syndrome was based on clinical, ECG, echocardiographic and enzymatic signs. All the patients accepted to be included in the present study and signed a consent formulary. The Clopidogrel resistance was determined by specific genetic laboratory tests., Results and Discussion: Of 80 cases, 4 patients were identified as normal responders (5%), 3 patients were low responders (3.75%), 58 patients were high responders (72.5%) and 15 patients were unpredictable (18.75%). In the high responders' group a lot of hemorrhagic disorders in different territories were identified. Normal responders had a good evolution. In patients with low response and unpredictable status the recurrence of angina and left ventricular failure as complications were frequent., Conclusions: The present study allowed a positive correlation between the haemorrhagic events and the high responder status to Clopidogrel. Low responder patients or those with an unpredictable phenotype had a worse evolution caused by the recurrence of angina or left ventricular failure.

Clopidogrel is an ADP receptor antagonist, an inhibitor of platelet activation and aggregation. The effect is due to its selective and irreversible blockade of the P2Y12 receptor. The concept of clopidogrel resistance emerged since several years ago. This biological finding has a very important impact especially in patients with acute coronary syndromes, explaining by this their worse evolution. Mechanisms of this resistance are very complex including: differences in intestinal absorption, hepatic conversion to the active metabolite through cytochrome 3A4 (CYP3A4) activity, drug interactions, individual variations in the activity of hepatic cytochrome P450 izoenzymes, platelet receptor polymorphisms and also clinical factors. According to this resistance patients are divided in two groups : "low or non-responders" (with a high risk of thrombosis) and "high--responders" (with a high risk of bleeding). Carriers of CYP2C19*2 or *3 alleles have been shown to respond poorly to standard doses of clopidogrel due to reduced metabolic activation of the drug. So, they are likely to develop subsequent thrombotic events. Starting from these, a lot of studies have been performed in order to elucidate the mechanisms of this resistance offering new perspectives regarding a proper administration of antiplatelet therapy in patients with acute coronary syndromes.

Unlabelled: Velo-Cardio-Facial Syndrome (VCFS) is characterized by congenital heart defects (CHD), palatal abnormalities, facial dysmorphism, neonatal hypocalcemia, immune deficit, speech and learning disabilities. SVCF is caused by microdeletion 22q11.2. Microdeletion is detected by fluorescence in situ hybridization (FISH). The highly variable phenotype makes diagnosis and selection for FISH more difficult., Aim: To retrospectively analyze and compare the phenotype of children with a clinical diagnosis of VCFS with/without 22q11 deletion; to verify the validity of literature guidelines and to describe combinations of clinical features that should lead to molecular analysis., Material and Methods: The present study was performed in 21 patients with a clinical diagnosis of VCFS. Methaphase chromosome spreads were prepared from phytohaemagglutinin stimulated lymphocyte culture by standard methods before FISH. The patients were divided into two groups according to FISH test: positive and negative., Results: The features commonly noticed in FISH positive patients were: palatal abnormalities/hypernasal speech, learning disabilities, facial dysmorphism, tapered fingers (6/6), CHD (5/6) and recurrent infections (2/6). In FISH negative patients the following were found: learning disabilities, CHD (12/15); facial dysmorphism (10/15), family history of CHD (7/15), short stature (6/15), hypocalcemia, tapered fingers (5/15), recurrent infections (3/15) and palatal cleft (2/15). In both groups, Tobias and McDonald-McGinn guidelines were positive., Conclusions: VCFS has a highly variable phenotype. Our study suggests that 22q11.2 deletion analysis by FISH should be performed in patients who have at least 2 (newborn)/3 (child, adult) specific criteria: CHD, hypocalcemia, palatal abnormalities, facial dysmorphism, learning disabilities, digital anomalies, and immune deficit.

Nephrotic syndrome, an entity described at the beginning of the 20th century, has still an unclear pathophysiology, genetic and immunologic factors being incriminated. Here we report three cases of nephrotic syndrome with genetic involvement. The article presented tremendous progress that have been made over the past few years in enhancing our understanding of the slit-diaphragm and podocyte biology and genetics involvement in nephrotic syndrome.

We present a retrospective study aimed to identify the correlation between de Vries clinical score and the detection of chromosomal abnormalities in mentally retarded (MR) children. We have used the score to identify patients who should be tested by karyotyping and subsequently MLPA (multiplex ligation dependent probe amplification) for subtelomeric rearrangements. Our group is formed of 36 children with variable MR associated with other anomalies. 18 children had chromosomal defects, whereas 18 had normal karyotypes. In the first group, total scores varied between 3 and 7. Chromosomal anomalies identified were: numerical (4) and structural (14). Chromosomes involved were: 1, 4, 5, 7, 8, 9, 17, X. Deletions were the most common and correlate with a greater score (> or = 4). Common clinical features were: short stature, microcephaly, nasal, ear and hand anomalies. In the second group the most frequent clinical feature was hand anomaly (61.2%) and cases with a high score have to be further tested (e.g. using MLPA) in order to identify minor defects. In our opinion a high score indicates the karyotype and then a MLPA testing. In conclusion, we present a retrospective study that proves the use of de Vries diagnostic score in the identification of chromosomal abnormalities in MR children.

Genetic causes of mental retardation (MR) are heterogeneous, but subtelomeric rearrangements are an important one. MLPA technique provides the best results in case detection. We have used MLPA to identify subtelomeric rearrangements in children with idiopatic MR. The protocol included: clinical selection; karyotype; antiFMRP test; MLPA. We have selected cases using de Vries diagnostic score. Patient data were recorded in a database. The group was formed of 142 MR children. In 24 (16.9%) the karyotype was abnormal. 16 cases (11.3%) presented speech delay/autism, but antiFMRP test was normal. 60 MLPA tests were done: 46 cases (76.7% were normal, 6 (10%) abnormal, 4 (6.7%) had polymorphism and 4 (6.7%) could not be interpreted. Clinical features of the cases identified are illustrated. In conclusion, the diagnostic score is useful in case selection for further testing and MLPA proves to be efficient in diagnosing subtelomeric rearrangements as a possible cause of idiopatic MR.

MLPA (Multiplex Ligation-dependent Probe Amplification) is a recently introduced method, based on PCR principle, useful for the detection of different genetic abnormalities (aneuploidies, gene deletions/duplications, subtelomeric rearrangements, methylation status etc). The technique is simple, reliable and cheap. We present this method to discuss its importance for a modern genetic service and to underline its multiple advantages.

Fragile X syndrome is the most common inherited cause of mental retardation. It is caused by a progressive expansion of polymeric (CGG)n trinucleotide repeats located on the FMR1 gene at Xq27.3. The spectrum of clinical involvement is broad, clinical diagnosis being difficult especially in young children. Hence, all cases of mental retardation without obvious cause should be tested for fragile X syndrome; the relatives of such a case need to be offered genetic counseling. Cytogenetic and molecular diagnostic tests are available. Recently, an immunocytochemical test has been described to identify fragile X patients, based on detection of FMR1 protein in cells using a monoclonal antibody. This method is used for screening, PCR based tests and Southern blot hybridization being the diagnostic tests for mutation and pre-mutation detection. Prenatal diagnosis is possible.

The authors present the case of a foetus with Jeune syndrome (asphyxiating thoracic dystrophy) in a woman with a previous deceased child with the same disease, and also with a normal sibling. The diagnosis was mentioned at 26 week of pregnancy, based on ultrasonographic findings: short proximal bones (under 3 percentiles), and a diminished thoracic circumference, (although greater than 10 percentiles for the gestational age). There was an interdisciplinary agreement for the therapeutic termination of the pregnancy, and the post-expulsion assessment confirmed the diagnosis. This case demonstrates a higher incidence of Jeune dystrophy than the one expected for an autosomal recessive disease, with 2 out of 3 children affected, instead of 25%. It also shows that the earliest change is the one regarding the shortened long bones, often difficult to notice before 20 weeks, fact which favors a detailed genetic sonogram done after this limit.

Rett syndrome is a form of X-linked mental retardation limited to females, expressed by postnatal microcephaly, moderate/severe mental retardation and prominent autistic features. We present a case to illustrate this rare entity, but also to discuss the suggestive behaviour and to underline the importance of diagnostic criteria. Our case associates porencephaly and positive CMV test that raised diagnostic difficulties in the beginning.

Turner's Syndrome is a rare chromosomal disorder of females (1 : 2500) characterized by short stature and the lack of sexual development at puberty. Other physical features may include a webbed neck, heart defects, kidney abnormalities, and/or various other malformations. Diagnosis should be considered in individuals with primary or secondary amenorrhea and adult women with unexplained infertility, particularly when such individuals also are short in stature. In childhood, growth hormone therapy is standard to prevent short stature as an adult. Estrogen replacement therapy usually is required, but starting too early can compromise adult height. The most frequent, the possibility of a good diagnosis appears at puberty. The early diagnosis needs the karyotyping as screening method. The correct treatment, which is made on time, has a good mental and social life influence.

Löwe syndrome is a form of X-linked mental retardation with short stature, cataracts, renal tubular dysfunction and hypotonia. We present 2 cases to illustrate this rare entity, but also to discuss the suggestive aspect of the face and to underline the importance of molecular tests for genetic counselling. Both cases associate ocular, cerebral and renal defects. Molecular tests changed the recurrence risk in the first family.

The case of a 75 years old woman with hereditary hemorrhagic telangiectasia (HHT) is presented. This condition is an autosomal dominant mucocutaneous and visceral fibrovascular dysplasia in which telangiectasia, arteriovenous malformations and aneurysms may be widely distributed throughout the cardiovascular system. It is usually recognized as a "triad" of telangiectasia, recurrent epistaxis and a family history of the disorder.