Annegret Kujat

A missense mutation in the ZFHX1B gene associated with an atypical Mowat-Wilson syndrome phenotype.

Mowat–Wilson syndrome (MWS) is a rare mental retardation—multiple congenital anomalies syndrome associated with typical facial dysmorphism. Patients can show a variety of other anomalies like short stature, microcephaly, Hirschsprung disease, malformations of the brain, seizures, congenital heart defects and urogenital anomalies. Mutations leading to haploinsufficiency of the ZFHX1B gene have been described as the underlying cause of this condition. We report on the clinical findings in a 2½‐year‐old boy with some aspects out of the MWS‐spectrum in addition to unusual anomalies and a novel missense mutation in the ZFHX1B gene.

Prenatal Diagnosis and Genetic Counseling in a Case of Spina Bifida in a Family with Waardenburg Syndrome Type I

Objective: Waardenburg syndrome type I (WS I) is an autosomal dominant inherited disorder with an incidence of 1:45,000 in Europe. Mutations within the PAX3 gene are responsible for the clinical phenotype ranging from mild facial features to severe malformations detectable in prenatal diagnosis. Methods: Here, we report a four-generation family with several affected members showing various symptoms of WS I. We diagnosed the syndrome first in a pregnant young woman; she was referred because of a spina bifida in prenatal diagnosis. We performed clinical genetic investigations and molecular genetic analysis in all available family members. Results: The phenotype displays a wide intra-familial clinical variability of pigmentary disturbances, facial anomalies and developmental defects. Molecular studies identified a novel splice site mutation within the PAX3 gene in intron 5 in all affected family members, but in none of the unaffected relatives. Conclusions: This case demonstrates the prenatal diagnosis of spina bifida in a fetus which leads to the initial diagnosis of WS I. Further studies could identify a private splice site mutation within the PAX3 gene responsible for the phenotype in this family.

DHPLC mutation analysis of phenylketonuria

Denaturing high-performance liquid chromatography (DHPLC) is a sensitive and fast method for the detection of mutations which has been successfully used for mutation screening in several disease-related genes. Phenylketonuria (PKU, OMIM* 261600; McKusick 1986) is one of the most common autosomal recessive disorders in Europe. Mutations in the PAH gene mainly involve point mutations. In this study we report the successful use of DHPLC to analyse rapidly the complete coding sequence of the PAH gene in a total of 125 unrelated patients with PKU.

Renal malformations in deletion 22q11.2 patients

DiGeorge anomaly (OMIM #188400) consists of hypoplasia of the thymus, T-Cell deficiency, hypoparathyroidism and structural heart defects [DiGeorge, 1965; Greenberg et al., 1984; Wilson et al., 1993]. Since establishment of fluorescence in situ hybridization (FISH), microdeletions in 22q11.2 were detectable in an increasing number of patients with DiGeorge anomaly, velocardiofacial syndrome (VCFS, syn. Shprintzen syndrome) and conotruncalanomaly-face syndrome [Scambler et al., 1991; Carey et al., 1992]. The 22q11.2 microdeletion syndrome occurs in 1/4,000 live births and constitutes the most frequent interstitial chromosomal aberration. A wide spectrum of clinical findings has been described in patients carrying the 22q11.2 deletion. The main symptoms are congenital heart defects, particularly conotruncal anomalies, immune deficiency and characteristic facial features. Congenital heart defects are present in over 70% of patients. Hearing loss, renal malformations, growth failure, and seizures are described less frequently. Also psychiatric disorders like schizophrenia are common in deletion 22q11.2 patients [Bassett et al., 2003]. We selected 31patientswith complete descriptions of their clinical phenotype. Patients with incomplete clinical data were excluded from this report. Of the 31 patients evaluated for microdeletion 22q11.2, 30 of them were referred to our clinic because of cardiovascular malformations and one because of velopharyngeal insufficiency and facial dysmorphisms. A complex heart defect associated with other malformations such as facial dysmorphisms, facial clefts and immune defects was reported in 27 patients at referral while in three patients an isolated heart defect was present. Routine cytogenetic analysis on Giemsa-banded chromosomes from cultured blood lymphocytes were performed on all 31 patients and were normal. FISH on metaphase chromosomes using DNA probes from the DiGeorge critical region, DGCR [TUPLE1, N25; Abbott/Vysis] for 22q11–13 deletion screening was performed. The clinical data of the patients were re-evaluated after cytogenetic and molecular cytogenetic investigations were completed to specify the phenotype. We found a microdeletion 22q11.2 in six out of the 31 selected patients (19%). Using the probes TUPLE1 and N25 (Abbott/Vysis) we found both loci to be deleted, spanning the complete DGCR. The affected patients showed typical facial features such as ear abnormalities and micrognathia. Two of these six patients were diagnosed with immune deficiencies and thymic hypoplasia. The clinical findings were summarized in Table I. In particular we noticed a high percentage of renal malformations in our group. In five out of six patients (80%) renal dysplasia, hydronephrosis and single kidney were recognized (seeTable I).Whileour sample size is small, this rateof renal anomalies in our group is higher than expected. Earlier studies demonstrated a percentage up to 40% for renal malformations in patients with a microdeletion 22q11 [Stewart et al., 1999; Wu et al., 2002]. Stewart et al. [1999] described an incidence of renal anomalies of 38.4% including bilateral duplex kidney, unilateral renal agenesis and dysplastic or small kidneys. The types of renal malformations noted in our study are similar to these of the European collaborative study [Ryan et al., 1997] and the study from Stewart et al. [1999]. However, Stewart et al. did not find a correlation between thymic and

Bladder exstrophy and Epstein type congenital macrothrombocytopenia: evidence for a common cause?

Boris Utsch,* Analisa DiFeo, Annegret Kujat, Stephanie Karle, Volker Schuster, Harald Lenk, Ulla Jacobs, Martin Müller, Jörg Dötsch, Wolfgang Rascher, Heiko Reutter, John A. Martignetti, Michael Ludwig, and Ralf-Bodo Tröbs Department of Pediatrics, University of Erlangen-Nuremberg, Erlangen, Germany Department of Human Genetics, Mount Sinai School of Medicine, New York, NY Department of Human Genetics, University of Leipzig, Leipzig, Germany Department of Pediatrics, University of Leipzig, Leipzig, Germany Department of Human Genetics, University of Bonn, Bonn, Germany Department of Clinical Biochemistry, University of Bonn, Bonn, Germany Department of Pediatric Surgery, University of Leipzig, Leipzig, Germany

Molecular and cytogenetic characterization of a non‐mosaic isodicentric Y chromosome in a patient with Klinefelter syndrome

We report on an adult male with Klinefelter phenotype and an isodicentric Y chromosome (47,XX,+idic(Y)(q12)), a combination which has to the best of our knowledge not been reported before. The patient was hospitalized in forensic psychiatry because of repeated delinquency, aggressive, aberrant and inappropriate behavior, and borderline intelligence. Molecular cytogenetic studies (FISH) showed that the SRY gene was present on both ends of the idicY, while there was only one signal for the Yq subtelomere probe. Molecular investigations by multiplex PCR, using STS markers covering the short and long arm of the Y chromosome did not indicate a deletion of Y chromosomal material. Molecular investigations of STR markers located on Xp22.3 and Xq28 indicated paternal origin of the additional X chromosome and an error in paternal meiosis I. Results of FISH analysis and molecular investigations are compatible with a phenotype as described for individuals with a 48,XXYY karyotype and support the findings that isodicentric Y chromosomes are frequently accompanied by other sex chromosomal abnormalities.

Different Phenotypes Including Gynecological Cancer in Three Female Patients with Peutz-Jeghers Syndrome and Mutations in the STK11 Gene

Background: Peutz-Jeghers syndrome (PJS), a rare hereditary disorder, is characterized by the occurrence of gastrointestinal hamartomatous polyps associated with mucocutaneous pigmentation. Patients are at an increased cancer risk not only for gastrointestinal but also for extraintestinal neoplasms. Patients and Results: We report on the clinical and molecular findings in 3 young female patients with PJS; 2 of them suffered from severe gynecological cancer. One patient died at the age of 29 years of an incurable mucin-producing cervical adenocarcinoma. Another patient had a papillary serous carcinoma of the ovary. In all patients, we identified corresponding mutations in the STK11 gene, 2 of them novel. Conclusion: PJS should be considered in differential diagnosis in young women with gynecological malignancies. Identification of STK11 mutations in patients and their relatives can help to improve the clinical management.

A microdeletion 22q11.2 can resemble Shprintzen-Goldberg omphalocele syndrome.

In the article entitled, ‘‘Shprintzen–Goldberg omphalocele syndrome: A new patient with an expanded phenotype,’’ Zelante et al. [2006] reported on a patient with Shprintzen–Goldberg omphalocele syndrome. Shprintzen and Goldberg [1979] described this malformation syndrome which includes dysmorphic facies, omphalocele, laryngeal and pharyngeal hypoplasia, scoliosis, and learning disabilities as major symptoms and is thought to be an autosomal dominant condition (OMIM 182210) (Table I). The patient of Zelante et al. [2006] had an expanded phenotype. We had the opportunity to evaluate a boy who showed resemblance to the Shprintzen–Goldberg omphalocele syndrome. Major symptoms were short stature, laryngeal abnormalities, an umbilical hernia, unilateral renal agenesis, highly pitched voice, and retarded motor and mental development. His facial features (Fig. 1) included a round face, brachycephaly, plagiocephaly, frontal bossing, hypertelorism, epicanthi, broad and high nasal bridge, downturned mouth, thin upper lip, micrognathia, and dysplastic low-set ears. Because of his unusual voice, a bronchoscopy was performed showing severe constrictions of the glottic airway. The height at age 2 6/12 years was 81 cm (5 cm <3rd centile) and the head circumference 50 cm (50th centile). The development was retarded: he started to walk at age 1 9/12 years and spoke the first few words at 2 years of age. Family history was unremarkable. Cytogenetic analysis of peripheral blood lymphocytes (G-banded chromosomes at 500 band resolution) showed a normal male karyotype 46,XY. FISH analysis (TUPLE1 and LSI DiGeorge N25 [Vysis, Abbott laboratories]) showed a deletion of the 22q11.2 region. Abnormalities associated with the 22q11 deletion syndrome are known to be extremely variable and are known to affect multiple body systems, including craniofacial and otolaryngeal structures, cardiovascular defects, skeletal, urogenital, and muscular abnormalities [Thomas and Graham, 1997]. Several features described in patients with Shprintzen– Goldberg omphalocele syndrome, such as laryngeal hypoplasia, membrane-like structures in the laryngeal lumen, anal atresia, and abnormal esophageal motility have been noted in patients with microdeletion 22q11.2. The diagnosis of Shprintzen–Goldberg omphalocele syndrome is based on the presence of omphalocele and pharynx/larynx hypoplasia as major diagnostic criteria. Further symptoms are unusual facies, abnormally high voice, scoliosis, hypotonia, and learning disabilities. Zelante et al. [2006] expanded the clinical phenotype, by describing a patient who had in addition an imperforate anus and dysphagia caused by an abnormal esophageal motility. These authors reported a normal male karyotype (46,XY) in their patient. Also FISH studies for subtelomeric rearrangements gave normal results, as did FISH analysis for del22q11.2. Chromosomal analysis is not mentioned in the original Shprintzen and Goldberg [1979] report. In conclusion, the present patient showed clinical features overlapping with Shprintzen–Goldberg omphalocele syndrome but in fact had a microdeletion of 22q11. Therefore, if Shprintzen–Goldberg omphalocele syndrome is considered in a patient, FISH studies to exclude a microdeletion 22q11.2 seem warranted.

Tetrasomie 18p@@@Tetrasomy 18p: 2-jähriges Mädchen mit einer psychomotorischen Entwicklungsretardierung, Spastik der unteren Extremität und kleineren Dysmorphiezeichen@@@A 2-year-old girl with retarded psychomotoric development, spasticity of the lower extremities and minor dysmorphic features

ZusammenfassungDie Tetrasomie 18p ist eine seltene numerische Chromosomenstörungen. Der Phänotyp resultiert aus dem Vorliegen eines kleinen überzähligen metazentrischen Markerchromosoms, eines Isochromosom 18p. Zu den typischen Merkmalen dieses chromosomalen Syndroms gehören Kleinwuchs, Mikrozephalie, mentale Retardierung sowie eine spastische Bewegungsstörung besonders der unteren Extremität. Wir berichten von einem 2-jährigen Mädchen, das aufgrund einer unklaren Entwicklungsstörung zur Vorstellung kam. Die klinisch-genetische Untersuchung ergab eine komplexe Entwicklungsstörung mit mild ausgeprägten Dysmorphiezeichen. Zur Abklärung führten wir eine Chromsomenanalyse mittels GTG-Bänderung durch. Diese ergab das Vorliegen eines zusätzlichen Markerchromosoms. Durch weitere Untersuchungen mittels Spectral Karyotyping (SKY™) und Fluoreszenz-in-situ-Hybridisierung (FISH) konnte das Chromosomenfragment als Isochromosom 18p identifiziert werden.AbstractTetrasomy 18p is a rare chromosomal disorder. The phenotype results from the presence of a small extra metacentric marker chromosome, an isochromosome 18p. The syndrome is characterized by mild to moderate mental retardation, microcephaly, minor dysmorphic features and spasticity of the lower limbs. Here we report on a 2-year-old girl, who was referred because of developmental delay and minor dysmorphic signs. Cytogenetic investigations revealed a small supernumerary marker chromosome. Further analysis using spectral karyotyping (SKY™) and fluorescence in situ hybridization (FISH) identified the marker chromosome fragment as an isochromosome 18p.

Potential Errors with Rapid Analysis Techniques: Partial Duplication 21q Resulting from a Paternal Paracentric Insertion Uncovered in Chorionic Villus Sampling by Fluorescence in situ Hybridization

We report on partial duplication 21q resulting from a paternal insertion identified during prenatal diagnosis. While performing interphase fluorescence in situ hybridization (I-FISH), we were able to identify 3 signals of the LSI 21 Spectrum Orange probe with chorionic villus sampling. Using standard cytogenetic analysis, I-FISH and GTG banding, structural aberrations in 21q in the parents and in the fetus could not be reliably determined. Applying metaphase fluorescence in situ hybridization (M-FISH), we identified a recombinant chromosome 21 carrying an interstitial duplication of the Down syndrome critical region inherited from the father. Both data from our analysis and published literature recommend the use of rapid testing methods such as I-FISH and standard cytogenetic analysis in prenatal diagnosis. It became obvious that I-FISH would not detect such a particular aberration. Thus, karyotyping, I-FISH and M-FISH should be performed in all Down syndrome cases.