201/2291. temporal bone histopathologic and genetic studies in Mohr-Tranebjaerg syndrome (DFN-1). OBJECTIVE: To describe the temporal bone histopathologic and genetic abnormalities in a case of Mohr-Tranebjaerg syndrome. BACKGROUND: Mohr-Tranebjaezrg syndrome (DFN-1) is an X-linked, recessive, syndromic hearing loss, characterized by postlingual sensorineural hearing loss with onset in childhood, followed in adult life by progressive dystonia, spasticity, dysphagia, and optic atrophy. The syndrome is caused by mutations in the DDP (deafness/dystonia peptide) gene, which are thought to result in mitochondrial dysfunction with subsequent neurodegeneration. The temporal bone pathologic changes in this syndrome have not been reported. methods: hearing loss developed in the patient at age 4, blindness at age 48, and dystonia at age 57. Genetic studies on peripheral blood showed a l51delT mutation in his DDP gene. He died at age 66. The right temporal bone was subjected to light microscopy and polymerase chain reaction-based analysis of the DDP gene sequence. RESULTS: There was near complete loss of spiral ganglion cells with loss of nearly all peripheral and central processes. Only 1,765 spiral ganglion cells remained (8.5% of mean normal for age). The organ of corti (including hair cells), stria vascularis, and spiral ligament were preserved. There was also a severe loss of Scarpa's ganglion cells with preservation of vestibular hair cells. The population of geniculate and trigeminal ganglion cells appeared normal. sequence analysis from temporal bone dna showed the 15ldelT DDP gene mutation. CONCLUSION: Sensorineural hearing loss in Mohr-Tranebjaerg syndrome is the result of a postnatal, progressive, severe auditory neuropathy. ( info) |
202/2291. Roberts-SC phocomelia syndrome. A severely growth retarded baby was born at 38 weeks gestation. He had multiple craniofacial anomalies, microbrachycephaly, phocomelia in the upper limbs and renal cysts visible on ultrasound. He died of recurrent apneas. The autopsy showed left sided multicystic dysplastic kidney and absence of one testis. Cytogenetic studies did not reveal any abnormality. The phenotypic features match those described in the Roberts-SC phocomelia syndrome. A literature review revealed that 50% of these patients have chromosomal defects and antenatal detection is possible on ultrasound and by chromosome analysis of the amniocytes. ( info) |
203/2291. Isochromosome (17)(q10) as the sole structural chromosomal rearrangement in a case of botryoid rhabdomyosarcoma. We describe a case of botryoid rhabdomyosarcoma with the karyotype 53,XX, 2, 5, 8, 12, 13, i(17)(q10), 19, 20. Only two cytogenetically analyzed cases of this tumor were previously reported and structural chromosomal abnormalities in each tumor were different. ( info) |
204/2291. Derivative (1;18)(q10;q10): a recurrent and novel unbalanced translocation involving 1q in myeloid disorders. We report two cases of hematological malignancies, comprising a case of myelodysplastic syndrome (MDS) that rapidly evolved into acute myeloid leukemia, and a case of myeloproliferative disorder (MPD), in which der(1;18)(q10;q10) was found as the sole acquired karyotypic abnormality. This observation indicates that the unbalanced translocation is a recurrent aberration in myeloid disorders. To the best of our knowledge, centromeric fusion between long arms of chromosomes 1 and 18, leading to a normal chromosome 18 substituted with a der(1;18) chromosome, is novel and has not been described in cancer. Mechanistically, either trisomy 1q or monosomy 18p that results from the translocation may potentially contribute to leukemogenesis. Finally, chromosomes with large constitutive heterochromatin bands such as chromosome 1 may be at risk of centromeric instability and be predisposed to centromeric fusion with other chromosomes. ( info) |
205/2291. Molecular characterization of tetralogy of fallot within Digeorge critical region of the chromosome 22. The purpose of this study was to determine whether the levels of heterozygosity and microdeletion of specific loci within the DiGeorge critical region (del22q11) are associated with different phenotypes of tetralogy of fallot (TF). Examinations were conducted on 84 sporadic TF patients and their unaffected parents for del22q11, using the following 9 simple tandem repeat polymorphic microsatellite markers: D22S420, D22S427, D22S941, D22S944, D22S264, D22S311, D22S425, D22S303, D22S257. The microdeletions were confirmed using quantitative PCR with markers TUPLE1, exon 2 of the UFD1L gene, and D22S264; the boundaries of these microdeletions were estimated using genotypic analyses of the unaffected family members. The del22q11 was identified in 14 patients (16.6%). The boundary of the shortest region of deletion overlap (SRO) in these 14 TF patients was identified, proximally using D22S427 and distally using the TUPLE 1 gene. The deletion of exon 2 of the UFD1L gene and TUPLE1 gene was identified in 13 patients (13/14 cases; 93%). The SRO in TF patients with del22q11 was at or close to the ADU breakpoint and centromeric to the UFD1L gene. The level of heterozygosity for the marker D22S944 in TF patients without del22q11 (n = 70) was found to be significantly lower than expected. overall, this study demonstrated the significantly low level of heterozygosity within DiGeorge critical region in TF patients with or without del22q11. Our results suggest that the genetic factors leading to DiGeorge/velocardiofacial syndrome might also be partly responsible for TF phenotypes. ( info) |
206/2291. association of a renal papillary carcinoma with a low grade tumour of the collecting ducts. This case report describes a 75 year old man who had a renal papillary carcinoma associated with a low grade tumour of the collecting ducts. These tumours showed different immunohistochemical patterns for epithelial membrane antigen, cytokeratin 19, and ulex europaeus lectin expression. In addition, cytogenetic findings were 47, XY, 7 <7> and 45, XY, -8, add(12)(q-ter)<10> for the papillary renal carcinoma and the low grade tumour of the collecting ducts, respectively. This is the first report where these two types of tumour are associated and cytogenetically distinguished. ( info) |
207/2291. Three cell line mosaicism involving structural and numerical abnormalities of chromosome 18 in a 3.5-year-old girl: 47,XX, 18/47,XX, del(18)(q22)/46,XX. We report on a 3.5-year-old girl with a mosaic karyotype including full trisomy 18, normal cells and a majority of cells with partial trisomy involving an extra chromosome 18 deleted at band q22. She had cardiac and CNS anomalies, dysmorphic facial features failure to thrive and developmental delay. A gastrostomy tube was placed at 2 years of age. The combination of improved nutrition and optimal developmental therapy has led to her sitting supported, attempting to stand and enhancement of her cognitive and non-verbal communication abilities. Molecular investigation of the patient and her parents using microsatellite analysis has led to the conclusion that, as expected, the additional copy of chromosome 18 constituting the full trisomic cell line is maternal meiosis I in origin. The data, however, indicate that in the trisomic cell line containing the deleted chromosome 18q, the structurally abnormal 18 was of paternal origin. We think this case is the first described with both structural and numerical trisomic mosaicism involving chromosome 18 in a liveborn infant. We propose a mechanism of origin and review the literature, comparing the clinical presentation of this case with individuals having full or partial trisomy 18. ( info) |
208/2291. Familial paroxysmal exercise-induced dyskinesia, epilepsy, and mental retardation in a family with autosomal dominant inheritance. Only few sporadic and familial cases of paroxysmal exercise-induced dyskinesia (PED) have been described in literature. PED associated with familial epilepsy has been rarely reported. We describe a family in which six members in different generations were affected by a long-lasting PED, with childhood onset in five cases. fasting and stress were also precipitating factors. All the subjects, moreover, showed epileptic seizures during childhood and adolescence. In addition, in all cases a condition of mild mental retardation was also documented, associated in some cases, with irritable and impulsive behaviour. Clinical, neurophysiological, neuroimaging and neuropsychological findings were reported. The homogeneous recurrence of this particular clinical picture in members of three generations emphasised a common genetic basis. In our patients, PED is transmitted as an autosomal dominant trait, with age-dependent penetrance, without evidence of genetic anticipation. The neurophysiological findings suggest a condition of hyperexcitability in the muscular and brain membrane, due to a ion channels disorder. ( info) |
209/2291. fluorescence in situ hybridization to assess transitional changes of aneuploidy for chromosomes 7, 8, 10, 12, 16, X and Y in metastatic prostate cancer following anti-androgen therapy. There have been few detailed studies conducted on the cell population in relation to cytogenetic changes between the pre- and post-treatment periods in patients with prostate cancer. We investigated numerical chromosome changes associated with anti-androgen therapy, using fluorescence in situ hybridization (FISH). FISH using chromosome-specific centromeric probes was used to assess transitional changes in the frequency of aneuploidy for chromosomes 7, 8, 10, 12, 16, X, and Y in prostate cancer during the pre- and post-treatment periods. Gains of chromosomes 7, 8 and 12 were notable in the pre-treatment samples (8 out of 9 cases in chromosome 7; 8 out of 9 cases in chromosome 8; 7 out of 9 cases in chromosome 12), while a notable reduction in the number of cells with extra copies of these chromosomes was observed in post-treatment specimens. Other chromosomes did not show noticeable change in their FISH signals at each phase of clinical treatment in all 9 cases. Changes in cell number with high ploidies of chromosome 7, 8 and 12 reflect the clinical effects of anti-androgen therapy at the early phase, which might explain the androgen dependency of metastatic prostate cancer cells. ( info) |
210/2291. Two unbalanced segregation products due to a maternal t(7;16)inv(16). We report a prenatal case of a maternally inherited abnormal chromosome 16, originally interpreted as a pericentric inversion only, but after family studies re-interpreted as a pericentric inversion (16) accompanied by an unbalanced (7;16) translocation. Because of the inversion 16 and an elder son with developmental delay and craniofacial dysmorphic features, in the past karyotyped as 46,XY, the chromosomes 16 of the mother and son were carefully re-examined. Using a whole chromosome 16 paint and sub-telomere probes of 16p and 16q, the karyotype of the mother was shown to be 46,XX,inv(16)(p11.2q23.2).ish t(7;16)(q36;p13.3)inv(16). Subsequently one chromosome 16 of the elder son appeared to be a der(16)t(7;16)(q36;p13.3). This is probably the result of a meiotic crossover between the chromosomes 16 in the mother. The prenatal karyotype was finally interpreted as 46,XY,inv(16)(p11.2q23.2).ish der(16)t(7;16)(q36;p13.3)inv(16). This is the same cytogenetic imbalance as his elder brother: a partial trisomy of chromosome 7 (q36-->qter) and a partial monosomy of chromosome 16 (p13.3-->pter). ( info) |