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Affected Family Members (affected + family_member)
Selected AbstractsIncreased number of offspring in first degree relatives of psychotic individuals: a partial explanation for the persistence of psychotic illnessesACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2009M. Weiser Objective:, As patients with psychotic illness have fewer offspring than controls, the persistence of psychotic illness is puzzling. We hypothesized that unaffected first-degree relatives of patients have more offspring than controls. Method:, Probands were 4904, individuals with non-affective psychotic disorders identified from a hospitalization registry. Unaffected first degree relatives and matched controls were identified from the Israeli Population Registry. The number of offspring of unaffected parents, biological siblings and controls was ascertained. Results:, Unaffected parents of psychotic patients had more offspring/person than controls; 4.5 ± 2.7 vs. 3.4 ± 2.2, P = 0.000. Unaffected parents from familial psychosis families (more than one affected family member) had 1.83 more offspring than controls; unaffected parents from non-familial psychosis families had 0.97 more offspring than controls (both P < 0.001). Conclusion:, These findings might imply that genes which increase susceptibility for schizophrenia may be associated with increased number of offspring, perhaps supplying a partial explanation for the persistence of psychosis. [source] Co-morbidity of Emery,Dreifuss muscular dystrophy and a congenital myasthenic syndrome possibly affecting the phenotype in a large Bedouin kindredEUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2007G. Ifergane Emery,Dreifuss muscular dystrophy (EDMD) is an X-linked humero-peroneal muscular dystrophy associated with contractures and cardiomyopathy. In a 90 member family, we found 11 affected male individuals, three of whom displayed areflexia and neurogenic electromyographic changes. Muscle biopsy performed in one case demonstrated type grouping suggestive of a neurogenic disorder. These three individuals and another family member, who suffers from mild, static limb weakness but is clinically and genetically unaffected by EDMD showed an abnormal incremental response of over 100% to tetanic stimulation. In contrast, one affected family member showed myopathic features on needle electromyography and no definite pathology in repetitive stimulation studies. The diagnosis of EDMD was established by demonstrating a 1712_1713insTGGGC mutation in the emerin gene. This family apparently expresses co-morbidity of EDMD with an exceptionally mild form of pre-synaptic congenital myasthenic syndrome resembling the Lambert,Eaton myasthenic syndrome (LEMS). The superimposed pre-synaptic disorder may have contributed to the development of the neurogenic features demonstrated in these patients. [source] Characteristics of frontotemporal dementia patients with a Progranulin mutationANNALS OF NEUROLOGY, Issue 3 2006Edward D. Huey MD Objective Mutations in the Progranulin gene (PGRN) recently have been discovered to be associated with frontotemporal dementia (FTD) linked to 17q21 without identified MAPT mutations. The range of mutations of PGRN that can result in the FTD phenotype and the clinical presentation of patients with PGRN mutations have yet to be determined. Methods In this study, we examined 84 FTD patients from families not known previously to have illness linked to chromosome 17 for identified PGRN and MAPT mutations and sequenced the coding exons and the flanking intronic regions of PGRN. We compared the prevalence, clinical characteristics, magnetic resonance imaging and 18-fluoro-deoxyglucose positron emission tomography results, and neuropsychological testing of patients with the PGRN R493X mutation with those patients without identified PGRN mutations. Results We discovered a new PGRN mutation (R493X) resulting in a stop codon in two patients. This was the only PGRN mutation identified in our sample. The patients with the PGRN R493X mutation had a rapid illness course and had predominant right-sided atrophy and hypometabolism on magnetic resonance imaging and 18-fluoro-deoxyglucose positron emission tomography. The affected father of one of the patients with the PGRN R493X mutation showed frontal and temporal atrophy without neurofibrillary tangles on neuropathological examination. Interpretation Known PGRN and MAPT mutations were rare and of similar prevalence in our sample (2 compared with 1/84). The patients with the PGRN R493X mutation had a clinical presentation comparable with other behavior-predominant FTD patients. The neuropathology of an affected family member of a patient with the PGRN R493X mutation appears not to be Alzheimer's disease. Ann Neurol 2006;60:374,380 This article includes supplementary materials available via the Internet at http://www.interscience.wiley.com/jpages/0364-5134/suppmat [source] Familial associations of rheumatoid arthritis with autoimmune diseases and related conditionsARTHRITIS & RHEUMATISM, Issue 3 2009Kari Hemminki Objective In the era of genome-wide association studies, familial risks are used to estimate disease heritability and the likelihood of candidate-gene identification. This study was undertaken to estimate associations of rheumatoid arthritis (RA) with any of 33 autoimmune diseases and related conditions among parents and offspring, singleton siblings, twins, and spouses. Methods The Multigeneration Register in Sweden was used as a reliable source of information on Swedish families throughout the last century. Data on autoimmune diseases in individual family members were obtained through linkage to the Hospital Discharge Register. The standardized incidence ratio (SIR) was calculated as a measure of the relative risk of RA in family members of patients with RA or any of 33 other autoimmune diseases or related conditions, as compared with the relative risk of RA in those lacking an affected family member. Results Among a total of 447,704 patients, 47,361 were diagnosed as having RA. The SIRs for RA were 3.02 in offspring of affected parents, 4.64 in siblings, 9.31 in multiplex families, 6.48 in twins, and 1.17 in spouses. Significant associations with the familial risk of RA in offspring according to parental proband were observed for ankylosing spondylitis (SIR 2.96), localized scleroderma (SIR 2.40), Sjögren's syndrome (SIR 2.25), systemic lupus erythematosus (SIR 2.13), systemic sclerosis (SIR 1.65), Hashimoto thyroiditis/hypothyroidism (SIR 1.54), pernicious anemia (SIR 1.53), sarcoidosis (SIR 1.40), psoriasis (SIR 1.36), Wegener's granulomatosis (SIR 1.34), and asthma or polymyalgia rheumatica (SIR 1.32). Conclusion This is the first study to compare the familial risks of RA in relation to a large number of autoimmune diseases and related conditions using data from a single population. The high discordant familial risks in this population suggest that there is extensive genetic sharing between RA and the associated diseases. [source] Phenotypic Comparison of Two Scottish Families with Mutations in Different Genes Causing Autosomal Dominant Nocturnal Frontal Lobe EpilepsyEPILEPSIA, Issue 4 2003Ailsa McLellan Summary: ,Purpose: Mutations in genes coding for the ,4 and ,2 subunits of the neuronal nicotinic acetylcholine receptor receptor (CHRN) are known to cause autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE). Here we examined the phenotypes in two families, from the same ethnic and geographic backgrounds, with ADNFLE as a result of mutations in these two different subunits of CHRN. Methods: All affected family members underwent a detailed clinical evaluation and review of available EEG, neuroimaging, and videotapes of seizures. The molecular study of family D is reported here; family S has a previously reported mutation in the ,2 subunit of CHRN. Results: A total of 16 individuals with ADNFLE were identified in the two families. In both families, seizure semiology, age at seizure onset, and the natural history of the seizure disorder was similar. Intrafamilial variation in terms of severity of epilepsy syndrome was present in both families. A significant number of individuals from each family had a history of psychological problems. The molecular study of family D revealed a Ser248Phe mutation in the ,4 subunit of CHRN. Conclusions: The epilepsy phenotype is not distinguishable in the two families who have ADNFLE as a result of mutations in genes coding for different CHRN subunits. This is likely to be due to the similar functional consequences of each mutation on the CHRN receptor. [source] Electroclinical Picture of Autosomal Dominant Nocturnal Frontal Lobe Epilepsy in a Japanese FamilyEPILEPSIA, Issue 1 2000Masatoshi Ito Summary: Purpose: Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is the first described partial epilepsy syndrome known to be due to a single gene mutation. We found a first Japanese ADNFLE family with a novel mutation of the neuronal nicotinic acetylcholine receptor (nAChR) ,4 subunit (CHRNA4) gene. The aim of this report is precisely to describe the electroclinical manifestations of ADNFLE in this family and to compare these findings with those of other families reported previously in the literature. Methods: Three affected family members were investigated electroclinically by close clinical observation, interictal EEG, video-EEG monitoring, magnetic resonance imaging, and single-photon-emission tomography. Information about other affected family members was obtained from either the spouse or the parents. Mutations within the CHRNA4 gene were examined in seven family members. Results: The clinical manifestations and diagnostic findings in the members of this family were consistent with ADNFLE. However, there were intrafamilial and interfamilial variations in clinical features. The seizures of the patients were brief tonic seizures, with hyperventilation in children and secondarily generalized tonic,clonic convulsions in adults. The onset of the children's seizures began in infancy and early childhood. The children's seizures were sometimes provoked by movement and sound stimulation, and did not respond to antiepileptic drugs. On the other hand, the adults' seizures disappeared spontaneously or were easily controlled with carbamazepine. Three children showed hyperactivity, and two children had mild mental retardation. All patients had impaired consciousness during their seizures and no auras. A novel missense mutation (c755C>T) in exon 5 of the CHRNA4 gene was found in four affected family members. Conclusions: The electroclinical pictures of a Japanese family with ADNFLE were basically the same as those of other families reported, but with slight differences. ADNFLE is probably not uncommon, and it is very likely that there are unidentified patients with this inherited disorder in Japan. [source] The tau S305S mutation causes frontotemporal dementia with parkinsonismEUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2008L. Skoglund Members of families with mutations in the tau gene are known to be heterogeneous in their clinical presentation, ranging from frontotemporal dementia to a clinical picture more resembling corticobasal degeneration or progressive supranuclear palsy. In this report, we describe a new phenotype for the tau S305S mutation, previously described as progressive supranuclear palsy. Clinically, the three affected family members showed alterations in personality and behaviour as well as cognitive decline and late levodopa-resistant parkinsonian symptoms, consistent with the diagnosis of frontotemporal dementia with parkinsonism linked to chromosome 17. One autopsied case displayed degeneration of the frontal and temporal lobes together with extensive tau pathology in both neurones and glial cells. Sarkosyl-soluble and -insoluble tau extracted from frontal cortex revealed a ratio shift with decreased levels of tau with three microtubule-binding repeats and increased levels of tau with four microtubule-binding repeats (4R tau). These findings provide further evidence for the clinical and pathological variation both within and between families with mutations in the tau gene. In addition, they support previous studies which demonstrate that the S305S mutation influences the splicing of tau exon 10 and results in an overproduction of 4R tau. [source] A locus for an auditory processing deficit and language impairment in an extended pedigree maps to 12p13.31-q14.3GENES, BRAIN AND BEHAVIOR, Issue 6 2010L. Addis Despite the apparent robustness of language learning in humans, a large number of children still fail to develop appropriate language skills despite adequate means and opportunity. Most cases of language impairment have a complex etiology, with genetic and environmental influences. In contrast, we describe a three-generation German family who present with an apparently simple segregation of language impairment. Investigations of the family indicate auditory processing difficulties as a core deficit. Affected members performed poorly on a nonword repetition task and present with communication impairments. The brain activation pattern for syllable duration as measured by event-related brain potentials showed clear differences between affected family members and controls, with only affected members displaying a late discrimination negativity. In conjunction with psychoacoustic data showing deficiencies in auditory duration discrimination, the present results indicate increased processing demands in discriminating syllables of different duration. This, we argue, forms the cognitive basis of the observed language impairment in this family. Genome-wide linkage analysis showed a haplotype in the central region of chromosome 12 which reaches the maximum possible logarithm of odds ratio (LOD) score and fully co-segregates with the language impairment, consistent with an autosomal dominant, fully penetrant mode of inheritance. Whole genome analysis yielded no novel inherited copy number variants strengthening the case for a simple inheritance pattern. Several genes in this region of chromosome 12 which are potentially implicated in language impairment did not contain polymorphisms likely to be the causative mutation, which is as yet unknown. [source] A novel mutation in the ATP2C1 gene is associated with Hailey,Hailey disease in a Chinese familyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 1 2009Zhou Jiang Liu MD Background, A three-generation Chinese family with Hailey,Hailey disease (HHD) was identified and characterized. The proband developed HHD with severe recurrent blisters and crusted erosions involving the body folds. Skin biopsy studies showed epidermal hyperkeratosis and defects in cell-to-cell adhesion. Three other members in the family were also affected with HHD and had the same clinical manifestations. The purpose of this study was to identify the pathogenic gene or mutation in the family. Methods, All exons and exon,intron boundaries of ATP2C1 were polymerase chain reaction (PCR) amplified and sequenced with DNA samples from the proband. Restriction fragment length polymorphism (RFLP) analysis for the intron 23,exon 24 boundary of ATP2C1 was performed in all family members and in 100 normal control subjects. Results, A novel 2-bp deletion (c.2251delGT) was detected in exon 24 of the ATP2C1 gene. The mutation was present in the three other affected family members and in two asymptomatic young carriers, but not in the other normal family members or the 100 normal controls. The mutation resulted in a frameshift change and led to the formation of a premature termination codon (PTC) four amino acid residues downstream from the sixth transmembrane domain. Conclusions, Our results indicate that the novel c.2251delGT (p.V751fs) mutation in the ATP2C1 gene is responsible for HHD in this Chinese family. This study expands the spectrum of ATP2C1 mutations associated with HHD. [source] Familial Hypocalciuric Hypercalcemia Caused by an R648stop Mutation in the Calcium-Sensing Receptor Gene ,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2002Mika Yamauchi Abstract In this study, we report an 84-year-old female proband in a Japanese family with familial hypocalciuric hypercalcemia (FHH) caused by an R648stop mutation in the extracellular calcium-sensing receptor (CaR) gene. At the age of 71 years, she presented with hypercalcemia (11.4 mg/dl), hypocalciuria (Cca/Ccr = 0.003), hypermagnesemia (2.9 mg/dl), and a high-serum parathyroid hormone (PTH) level (midregion PTH, 3225 [160,520] pg/ml). At the age of 74 years, a family screening was carried out and revealed a total of 9 hypercalcemic individuals (all intact PTH values <62 pg/dl) among 17 family members tested, thus, being diagnosed as FHH. Two and one-half of three clearly enlarged parathyroid glands were resected, because persistently high PTH levels (intact PTH, 292 pg/ml; midregion PTH, 5225 pg/ml) and the presence of a markedly enlarged parathyroid gland by several imaging modalities (ultrasonography, computed tomography [CT], magnetic resonance imaging [MRI], and subtraction scintigraphy) suggested coexistent primary hyperparathyroidism (pHPT); however, hypercalcemia persisted postoperatively. Histological and immunohistochemical examination revealed that the resected parathyroid glands showed lipohyperplasia as well as normally expressed Ki67, vitamin D receptor (VDR), and the CaR. Sequence analysis disclosed that the proband and all affected family members had a heterozygous nonsense (R648stop) mutation in the CaR gene. This mutation is located in the first intracellular loop; thus, it would be predicted to produce a truncated CaR having only one transmembrane domain (TMD) and lacking its remaining TMDs, intracellular loops, and C-terminal tail. Western analysis of biotinylated HEK293 cells transiently transfected with this mutant receptor showed cell surface expression of the truncated protein at a level comparable with that of the wild-type CaR. The mutant receptor, however, exhibited no increase in intracellular free calcium concentration (Ca2+i) when exposed to high extracellular calcium concentrations (Ca2+o). The proband's clinical course was complicated because of associated renal tubular acidosis (RTA) and nephrotic syndrome. However, it was unclear whether their association affected the development of elevated serum PTH and parathyroid gland enlargement. This report is the first to show that an R648stop CaR mutation yields a truncated receptor that is expressed on the cell surface but is devoid of biological activity, resulting in FHH. [source] Novel mutations in the Na+, K+ -ATPase pump gene ATP1A2 associated with familial hemiplegic migraine and benign familial infantile convulsionsANNALS OF NEUROLOGY, Issue 3 2003Kaate R. J. Vanmolkot Msc Familial hemiplegic migraine (FHM) is a rare, severe, autosomal dominant subtype of migraine with aura. Up to 75% of FHM families have a mutation in the P/Q-type calcium channel Cav2.1 subunit CACNA1A gene on chromosome 19p13. Some CACNA1A mutations also may cause epilepsy. Here, we describe novel missense mutations in the ATP1A2 Na+,K+ -ATPase pump gene on chromosome 1q23 in two families with FHM. The M731T mutation was found in a family with pure FHM. The R689Q mutation was identified in a family in which FHM and benign familial infantile convulsions partially cosegregate. In this family, all available affected family members with FHM, benign familial infantile convulsions, or both, carry the ATP1A2 mutation. Like FHM linked to 19p13, FHM linked to 1q23 also involves dysfunction of ion transportation and epilepsy is part of its phenotypic spectrum. [source] A novel mutation in the third extracellular domain of the tumor necrosis factor receptor 1 in a Finnish family with autosomal-dominant recurrent feverARTHRITIS & RHEUMATISM, Issue 4 2002Hanna Nevala Objective To investigate the presence of TRAPS (tumor necrosis factor receptor,associated periodic syndrome), which is a recently defined, dominantly inherited autoinflammatory syndrome caused by mutations in the tumor necrosis factor receptor superfamily 1A gene (TNFRSF1A, CD120a), in a Finnish family with recurrent fever. Methods The TNFRSF1A gene was sequenced in both affected and unaffected family members. Flow cytometry and enzyme-linked immunosorbent assay analyses were used to assess membrane expression and serum levels of the TNFRSF1A protein, respectively. Results A missense mutation in exon 4, located in the third extracellular domain of TNFRSF1A and resulting in an amino acid substitution (F112I) close to a conserved cysteine, was found in all 4 affected family members and in 1 asymptomatic individual. The mutation was clearly associated with low levels of soluble TNFRSF1A as well as with the clinical symptoms of recurrent fever and abdominal pain. Impaired shedding of TNFRSF1A after phorbol myristate acetate stimulation was detected in blood granulocytes and monocytes from the 3 adult family members with the mutation, but in the child bearing the mutation and showing clinical symptoms of recent onset, the shedding defect was less marked. Conclusion TRAPS should be suspected in any patient who presents with a history of intermittent fever accompanied by unexplained abdominal pain, arthritis, or skin rash, particularly in the presence of a family history of such symptoms. Screening for low serum levels of soluble TNFRSF1A identifies individuals who are likely to have TNFRSF1A mutations. [source] Novel heteroplasmic mutation in the anticodon stem of mitochondrial tRNALys associated with dystonia and stroke-like episodesACTA NEUROLOGICA SCANDINAVICA, Issue 4 2010A. Gal Gal A, Pentelenyi K, Remenyi V, Pal Z, Csanyi B, Tomory G, Rasko I, Molnar MJ. Novel heteroplasmic mutation in the anticodon stem of mitochondrial tRNALys associated with dystonia and stroke-like episodes. Acta Neurol Scand: 2010: 122: 252,256. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives,,, We report a novel heteroplasmic mitochondrial tRNALys mutation associated with dystonia, stroke-like episodes, sensorineural hearing loss and epilepsy in a Hungarian family. Material and methods,,, A 16-year-old boy, his brother and mother were investigated. Thorough clinical investigation as well as electrophysiological, neuroradiological and myopathological examinations were performed. Molecular studies included the analysis of the DYT1, DDP1/TIMM8A (deafness-dystonia peptid-1) genes and mitochondrial DNA (mtDNA). Results,, The mtDNA analysis of the proband revealed a heteroplasmic A8332G substitution in the anticodon stem of the tRNALys gene. The mutation segregated in all affected family members. Besides this mutation 16 further mtDNA polymorphisms were detected. Complex I activity of the patient's fibroblast cultures showed decreased activity confirming mitochondrial dysfunction. Conclusion,, The novel A8332G heteroplasmic mutation is most likely a new cause of dystonia and stroke-like episodes due to mitochondrial encephalopathy. The synergistic effect of the G8697A, A11812G and T10463C single nucleotide polymorphisms may modify the phenotype. [source] Dystrophia Helsinglandica , corneal morphology, topography and sensitivity in a hereditary corneal disease with recurrent erosive episodesACTA OPHTHALMOLOGICA, Issue 4 2010Waldir Neira Abstract. Purpose:, The aim of this study was to describe the morphology, corneal topography and sensitivity in individuals with Dystrophia Helsinglandica. This autosomal dominant corneal disease is characterized by recurrent corneal erosive episodes and progressive subepithelial fibrosis not significantly affecting visual acuity. Methods:, The corneas of nine affected and nine unaffected individuals were examined using slit-lamp biomicroscopy, in vivo confocal microscopy (IVCM) and videokeratography. Corneal mechanical sensitivity was also measured using a non-contact esthesiometer. Results:, Slit-lamp biomicroscopy revealed that the affected individuals represented different stages of corneal changes, from a nearly normal cornea to subepithelial fibrosis of the central cornea. Corneal changes in affected individuals did not significantly decrease the best spectacle-corrected visual acuity. In vivo confocal microscopy detected morphological changes in the epithelium and stroma. Subepithelial opacity formation including altered keratocytes could be found in the anterior stroma in all affected eyes. With the exception of two eyes (one affected and one unaffected), all videokeratographies showed irregular astigmatism. Corneal sensitivity was significantly lower in affected individuals (p = 0.01). Age and corneal sensitivity showed no correlation. Conclusion:, The main morphological findings in affected individuals were discrete and progressive subepithelial fibrosis, in the in vivo confocal microscope corresponding to optically dense extracellular matrix and activated keratocytes. Subbasal nerve morphology was changed in the affected family members who also showed a decreased corneal sensitivity. The findings are per se not specific to the disease. The changes probably reflect a healing response to erosive events on the corneal surface influenced by the genotype. [source] A new mutation in the linker 12 domain of keratin 5 in a Chinese family with Weber,Cockayne epidermolysis bullosa simplexCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 5 2004J.-G. Li Summary A previously undescribed missense mutation was detected in the L12 domain of keratin 5 (K5) in a Chinese family with Weber,Cockayne epidermolysis bullosa simplex. Direct sequencing of the PCR products identified a single base substitution (983A,G) that changes the aspartic acid residue at codon 328 to glycine in all affected family members, while no mutation was observed either in the healthy individual or 50 unrelated control samples. Asp328 of K5 is remarkably conserved among all type II keratins. D328G is the fourth mutation found to affect this residue in K5-related epidermolysis bullosa simplex, indicating the importance of Asp328 for K5 structure and the dramatic effect that fine changes can have on keratin intermediate filament integrity. [source] Novel and recurrent p14ARF mutations in Italian familial melanomaCLINICAL GENETICS, Issue 6 2010F Binni Binni F, Antigoni I, De Simone P, Majore S, Silipo V, Crisi A, Amantea A, Pacchiarini D, Castori M, De Bernardo C, Catricalà C, Grammatico P. Novel and recurrent p14ARF mutations in Italian familial melanoma. CDKN2A and CDK4 are the only known high-penetrant genes conferring proneness to cutaneous melanoma. The CDKN2A locus consists of four exons and encodes several alternate transcripts, two of which are p16INK4a and p14ARF, and originate from different open reading frames. Exon 1, is specific for p16INK4a, while exon 1, characterizes p14ARF. Most CDKN2A mutations are located in exons 1, and 2, while exon 1, variations have been identified in rare melanoma-prone pedigrees. In a previous study, we investigated 155 Italian melanoma cases, including 94 familial melanomas (FAMs) and 61 sporadic multiple primary melanomas (MPMs), for p16INK4a/CDK4 germline alterations and identified 15 p16INK4a and 1 CDK4 point mutations. In the present work, we extended our search to p14ARF mutations and CDKN2A deletions in the remaining samples. We identified the recurrent g.193+1G> A mutation in two FAM cases, while an additional pedigree displayed the previously undescribed variant g.161G> A. Multiplex ligation-dependent probe amplification (MLPA) screening for copy variations resulted negative in all cases. In Italy, the overall frequency of p14ARF mutations is 3.2% in FAM and 0% in sporadic MPM. Re-evaluation of our patients' cohort emphasizes that the chance of identifying CDKN2A/CDK4 mutations in FAM is mainly influenced by the number of affected family members and the presence of one or more MPM cases. Accordingly, mutation rate rises to 61% in selected cases. Further studies are expected in order to investigate CDKN2A rarer mutations, including atypical deletions and inherited epimutations. [source] Homozygous feature of isolated triphalangeal thumb,preaxial polydactyly linked to 7q36: no phenotypic difference between homozygotes and heterozygotesCLINICAL GENETICS, Issue 1 2009CN Semerci Preaxial polydactyly is a common limb malformation in humans with variable clinical expression. Different types of triphalangeal thumb-preaxial polydactyly phenotypes were mapped to the chromosome 7q36 region. We studied a large Turkish family of 69 individuals, of whom 22 individuals were affected. In all, 11 affected family members were clinically and radiologically evaluated. All affected individuals had a triphalangeal thumb and a preaxial (hypoplastic) extra digit bilaterally, with minimal intrafamilial variation. No feet involvement was observed. Linkage and haplotype analyses using 20 informative meioses confirmed the 7q36 region contained the LIMBR1 gene. Maximum logarithm of the odds (LOD) scores were obtained with DNA markers D7S550 and D7S2423. We have further identified a novel C to T alteration at position 4909 bp in the critical zone of polarizing activity regulatory sequence (ZRS) region, in the intron 5, of the LMBR1 gene. One affected male with homozygous status and no phenotypic difference from affected family members with heterozygous status represented the first homozygote case of the triphalangeal thumb-preaxial polydactyly phenotype. [source] A novel nonsense mutation in the EYA1 gene associated with branchio-oto-renal/branchiootic syndrome in an Afrikaner kindredCLINICAL GENETICS, Issue 1 2006JC Clarke Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by the associations of hearing loss, branchial arch defects and renal anomalies. Branchiootic (BO) syndrome is a related disorder that presents without the highly variable characteristic renal anomalies of BOR syndrome. Dominant mutations in the human homologue of the Drosophila eyes absent gene (EYA1) are frequently the cause of both BOR and BO syndromes. We report a South African family of Afrikaner descent with affected individuals presenting with pre-auricular abnormalities and either hearing loss or bilateral absence of the kidneys. Genetic analysis of the pedigree detected a novel EYA1 heterozygous nonsense mutation in affected family members but not in unaffected family members or a random DNA panel. Through mutational analysis, we conclude that this particular mutation is the cause of BOR/BO syndrome in this family as a result of a truncation of the EYA1 protein that ablates the critical EYA homologous region. To the best of our knowledge, this is the first case of BOR/BO syndrome reported in Africa or in those of the Afrikaner descent. [source] | |||||||||||||||||||||||||