A novel TTC37 mutation causing clinical symptoms of trichohepatoenteric syndrome such as pyoderma gangrenosum and immunodeficiency without severe diarrhea

No disponible

A FURTHER PATIENT OF PURE 15q DELETION: CLINICAL AND MOLECULAR CYTOGENETIC FINDINGS.

A deletion of the distal long arm of chromosome 15 is generally reported with the formation of ring chromosome 15, whereas an isolated 15q deletion is rarely described. Here we report an 11 year-old girl, from non-consanguineous parents, who was referred to the Pediatric Genetics Department with growth retardation and multiple congenital abnormalities. In her medical history, she had a cleft palate, hip dislocation and crossed renal ectopia. Dysmorphological evaluation revealed a triangular face, low-set ears, fissured cleft tongue, micrognathia, proximally placed hypoplastic thumbs, genu valgus, 2-3 toe skin syndactyly, clinodactyly and nail hypoplasia. Speech problems were also noticed. The karyotype was normal. Subtelomeric fluorescent in-situ hybridisation (FISH) analysis showed a de novo terminal deletion about 755 kb. Furthermore, the breakpoint was located within the CHSY1 gene that is responsible for Temtamy preaxial brachydactyly syndrome which shares clinical features with 15qter deletion syndrome. To the best of our knowledge, this deletion is the smallest among reported patients. It is considered that the patient presented here significant contribution to phenotype-genotype correlation in 15q deletion patients.

GENETIC COUNSELLING IN FEINGOLD SYNDROME AND A NOVEL MUTATION.

Feingold syndrome (FS) is an autosomal dominant hereditary disorder characterised by finger and toe abnormalities, microcephaly, facial dysmorphism, gastrointestinal atresias such primarily as oesophageal and/or duodenal atresia and mild to moderate mental retardation. Approximately 60% of cases have an affected parent. MYCN is the only gene in which mutations are known to cause FS. In this report, we present a case with Feingold Syndrome having a novel mutation in MYCN gene and discuss genetic counselling and prenatal diagnosis due to pregnancy of the patient's mother.

TWINS WITH KLEEFSTRA SYNDROME DUE TO CHROMOSOME 9q34.3 MICRODELETION.

Kleefstra or 9q subtelomeric deletion syndrome (9qSTDS) is a rare microdeletion syndrome. The most prominent phenotypic features include hypotonia, developmental retardation, as well as typical dysmorphic face. It has been shown that terminal deletions of the chromosome 9q34.3 region, or EHMT1 gene mutations, lead to Kleefstra syndrome. We present 16-month-old twin sisters, one of whom had originally been referred for Down syndrome screening due to hypotonia, growth and development retardation, dysmorphic facial signs, and accompanying congenital heart disease. They were subsequently diagnosed as Kleefstra syndrome based on subtelomeric FISH analysis. In conclusion, Kleefstra syndrome should be considered in the differential diagnosis of Down syndrome because it presents with very similar phenotypic features.

Genome-wide copy number variation analysis in idiopathic intellectual disability/multiple congenital anomalies.

New array technologies have facilitated the analysis of submicroscopic chromosomal imbalances and structural variants. Copy number variation (CNV) analysis can reveal genetic imbalances in up to 10% of cases involving intellectual disability (ID), with or without multiple congenital anomalies (MCA). Here we present 4 cases, diagnosed by CNV analysis using Affymetrix Genome Wide Human SNP 6.0 array, and their parents. CNVs ranging from 18 to 196 per subject, with a size range of 100kb- 6093kb, were detected in all cases. One case revealed inherited CNVs, whilst de novo ins/dels were found in the other three which may be causative factors in the development of clinical pictures. Microarray technology may help to reveal the etiology of ID and is a potentially useful diagnostic tool for patients with ID/MCA.

Results of fifteen-year follow-up from a single center: findings and risks for tumor development in isolated hemihyperplasia cases.

Isolated hemihyperplasia is abnormal asymmetric growth of one or more parts of the body without any underlying disease. The risk for the development of embryonal tumor is increased in the subjects with isolated hemihyperplasia. The study presented here retrospectively evaluated the clinical data and the risk for tumor development in the cases with isolated hemihyperplasia. 24 cases with isolated hemihyperplasia were retrospectively evaluated. An extremity segment has been involved in 16.7%, an extremity has been entirely involved in 37.5%, more than one extremity have been involved on the same side in 16.7%, and definitely half of the body including the face has been involved in 25% of the patients, whereas one side of the face has been involved in only one case. Wilms tumor in the left abdomen (4.2%) was developed in one case. Isolated hemihyperplasia is a rare clinical picture that enhances the risk for the development of embryonal tumors.

A twin sibling with Prader-Willi syndrome caused by uniparental disomy conceived after in vitro fertilization.

The use of assisted reproductive technologies (ART) has increased gradually in the treatment of infertility worldwide. On the other hand ART has been found to be associated with an increased risk of congenital malformations including imprinting defects as well. Although a number of imprinting syndromes have been reported to be related with ART, no case with uniparental disomy (UPD) caused Prader-Willi syndrome (PWS) [OMIM ID: 176270] has been reported in the literature. Here we present a dizygotic twin in which one of them was born with maternal UPD15 following ART. The proband was a 2-year-old boy who had feeding difficulties, generalized hypotonia, frontal bossing, broad forehead, small hands and feet. Laboratory investigations revealed minimal dilatation in 3rd and 4th ventricles and corpus callosum hypoplasia in magnetic resonance imaging, supravalvular pulmonary stenosis in echocardiography and pelvicaliectasia in the USG examinations. Methylation and microsatellite markers analyses showed maternal UPD for chromosome 15. Here we report, for the first time UPD caused PWS patient born after ART.

Subtelomeric rearrangements in patients with idiopathic intellectual disabilitiy/ multiple congenital anomalies and recurrent miscarriages: seven years' experience.

Cryptic subtelomeric anomalies are a significant cause of idiopathic intellectual disability and/or multiple congenital anomalies (ID/MCA) and multiple miscarriages (MM). Effective preselection of patients is essential as the cost of subtelomeric testing is high and it is labor-intensive. Therefore, the aim of this study is to evaluate the frequency of subtelomeric anomalies by using commercial FISH probes in 151 patients of ID/MCA and 32 couples with MM who were referred to a genetic center during 7-year period and to determine whether performing subtelomeric testing is feasible for these groups of patients. We assessed the clinical information of all referrals including family history, physical examination, facial dysmorphism, congenital malformations and scored the ID/MCA patients according to the criteria suggested previously. The etiology was not elucidated and all patients had normal karyotypes. Subtelomeric deletions were found in 10 patients in ID/MCA group (6.62%). These were deletions of 14qter (2 patients), 18qter (2 patients), 18pter (2 patients), 15qter, 7pter, 8pter and 4qter. The clinical information of all patients having deletions has been summarized and confined with the current literature. No anomaly was detected in the MM group. In conclusion, the prevalence of subtelomeric anomalies in ID/MCA group in this study is consistent with the literature and subtelomeric FISH analysis is feasible in determining their etiology when a checklist is used. Besides, assessment of the genetic basis of ID/MCA had lead the prevention of the recurrence of such conditions in selected families as well as elucidating novel genetic causes of ID.

Partial trisomy 2p24-->pter and monosomy 18q22.1- qter resulting from parental translocation.

This is a report of a 6 month-old boy with a partial trisomy 2p24-->pter and monosomy 18q22-->qter. This is the first case presenting this unbalanced translocation with phenotypic features. The patient had growth and developmental retardation, facial dysmorphism, cleft palate, congenital cardiopathy, hypospadias, evantration of diaphragm and deafness. Cranial MRI showed mild ventricular dilatation. Cytogenetic analysis of the patient and his parents revealed a karyotype 46,XY, der(18), t(2;18)(p24;q22)mat in the patient. Subtelomeric FISH analysis confirmed the cytogenetic findings. Phenotypic features were consistent with either partial trisomy 2p or deletion 18q.

Analysis of the sphingomyelin phosphodiesterase 1 gene (SMPD1) in Turkish Niemann-Pick disease patients: mutation profile and description of a novel mutation.

Niemann-Pick disease (NPD) is a lysosomal storage disorder that results from the deficiency of a lysosomal enzyme, acid sphingomyelinase. Niemann-Pick disease type A and B is caused by mutations in the sphingomyelin phosphodiesterase gene (SMPD1) coding for ASM. The aim of this study was to evaluate the spectrum of SMPD1 gene mutations in Turkish NPD patients and to study genotype-phenotype associations. We present a molecular analysis of 10 Turkish NPD type A/B patients. Four of the patients had type A and six had type B NPD. All mutant SMPD1 alleles were identified, including 5 different mutations, 1 of which was novel. These mutations included three missense mutations: c.409T>C (p.L137P), c.1262 A>G (p.H421R) and c.1552T>C (p.L549P), a common frameshift mutation in codon 189, identified in three patients, is caused by the deletion of the 567T, introducing a stop codon 65 amino acids downstream (p.P189fsX65), and a novel frameshift mutation c.1755delC (p.P585PfsX24) which was not reported previously.

Genome wide analysis in a discordant monozygotic twin with caudal appendage and multiple congenital anomalies.

Caudal appendage is a rare dysmorphic feature of which etiologic mechanisms are not well understood. Here we report monozygotic (MZ) twin brothers who are discordant for the caudal appendage and multiple congenital anomalies. Twins were the product of a 33 weeks of gestation, monochorionic-diamniotic pregnancy. On admission the proband had micrognathia, beaked nose, hypospadias, caudal appendage and juxtaductal aorta coarctation. At birth, he was small for gestational age and he had transient hypothyroidism which was detected in the newborn period. Karyotype analysis showed 46,XY. Monozygosity was shown by 15 microsatellite markers plus amelogenin (AmpFlSTR Identifiler PCR Amplification Kit, Applied Biosystems). Genome-wide copy number analysis of the twins by DNA-DNA hybridization of whole genomic DNA (NimbleGen Human CGH 385K WG-T v2.0 array) showed a significant difference at two neighboring probes with Log2 ratio: 0.72088 which are located on chromosome 3p12.3. Further analysis by high resolution of chromosome 3 array (Roche NimbleGen Human HG18 CHR3 FT Median Probe Spacing 475 bp) and quantitative PCR analysis did not confirm the deletion.

Determination of fetal rhesus d status by maternal plasma DNA analysis.

In this study, we assessed the feasibility of fetal RhD genotyping by analysis of cell-free fetal DNA(cffDNA) extracted from plasma samples of Rhesus (Rh) D-negative pregnant women by using real-time polymerase chain reaction (PCR). Fetal genotyping was performed on 30 RhD-negative women between 9 and 39 weeks of gestation who were referred to us for invasive testing [amniocentesis/chorionic villi sampling (CVS)]. The fetal RHD genotype was determined based on real-time PCR method. Exons 7 and 10 of the RHD and SRY genes were targeted. Among the pregnant women, 12 were carrying male and 17 were carrying female fetuses. Out of 29 pregnant women, 21 had RhD-positive and nine had RhD-negative fetuses. One sample (case 12, whose blood group was found to be AB Rh [+]) was excluded due to controversial results from repeated serological analyses. All prenatal results were in concordance with postnatal RhD status and fetal sex without false- positive or -negative results. Performing real-time PCR on cffDNA showed accurate, efficient and reliable results, allowing rapid and high throughput non invasive determination of fetal sex and RhD status in clinical samples.

A new clinical presentation associated with pontine clefting, hyperpigmentation and short stature in addition to craniofacial, cardiac and developmental anomalies.

We report on a 13-year-old girl who was the first child of nonconsanguineous parents, and who suffered from short stature accompanied with mental retardation, generalized hyperpigmentation of the skin and craniofacial findings. Her cardiological examination revealed atrial septal defect, mitral valve prolapsus and atrial septal aneurysm. Brain scans revealed dilatation of the third and lateral ventricles and a pontine cleft. Growth hormone (GH) deficiency was observed during the evaluation of GH/IGF-I axis. All the laboratory tests performed including metabolic screening, conventional karyotype and oligonucleotide array were normal. Mutation analysis of the C2ORF3 7 gene revealed no mutation. The clinical signs seen in this patient likely represent a new dysmorphological syndrome which has not been previously described.

Unusual presentation of biliary atresia splenic malformation syndrome with autosomal dominant hypospadias.

Biliary atresia is associated with polysplenia in 2-10% of cases and is defined as Biliary Atresia Splenic Malformation syndrome (BASM). The main features of BASM syndrome include extrahepatic biliary atresia and polysplenia besides the characteristic findings of laterality anomalies, cardiac anomalies, intraabdominal vascular anomalies, pancreatic anomalies and malrotation. Here we present a 6-month-old male patient with BASM having atrial septal defect, umblical hernia, inguinal hernia, and hypospadias. Clinical history revealed that his father also had hypospadias which showed a rare form of autosomal dominant inheritance. The karyotype was normal and the molecular analysis of CFC1 gene revealed no mutation. We emphasize the importance of a detailed physical examination in cases with BASM.

Oculocerebral hypopigmentation syndrome maps to chromosome 3q27.1q29.

BACKGROUND: In 1967, Cross et al. [J Pediatr 1967;70:398-406] reported four siblings with intellectual disability, microcephaly, neurologic and ocular disorders, and hypopigmentation involving skin and hair. This novel entity, known as oculocerebral hypopigmentation syndrome (OCHS) or Cross syndrome (OMIM 257800), is assumed to be autosomal recessive. However, its genetic cause is still unknown. CASE REPORT: A 4-year-old girl is reported with OCHS, a history of recurrent infections and vertebral fusion of L4-L5. Central nervous system and cardiac imaging as well as metabolic screening were normal. Microscopic hair investigations did not show any melanin deposit defects. RESULTS: Using molecular cytogenetics, we detected a de novo interstitial del(3)(q27.1q29) of the paternal chromosome. To our knowledge, this is the first molecular genetics finding in a patient with OCHS. Here we discuss the genotype-phenotype correlations and suggest candidate genes for this disorder. CONCLUSION: Investigating further patients would enable fine-mapping the OCHS locus and identifying its putative gene.