Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Lowe oculocerebrorenal syndrome (OCRL; McKusick 309000) is an X-linked disorder characterized by congenital cataracts, muscular hypotonia, mental retardation, and Fanconi syndrome of the renal tubules. A pair of yeast artificial chromosomes (YACs) that span the Xq25-q26 translocation breakpoint in a female with OCRL were used as probes to screen cDNA libraries made from bovine lens and human kidney. The methods used to prepare the YACs as probes and to screen the libraries are presented in detail. Two different transcripts were found that map to the region around the Xq25-q26 breakpoint. These transcripts are now being studied to determine whether one or the other is a candidate gene for OCRL.
 ...
PMID:Isolation of cDNA sequences around the chromosomal breakpoint in a female with Lowe syndrome by direct screening of cDNA libraries with yeast artificial chromosomes. 152 13

A Hispanic girl with Lowe oculocerebrorenal syndrome (OCRL), an X-linked recessive condition characterized by cataracts, glaucoma, mental retardation, and proteinuria, is reported. A balanced X;20 chromosomal translocation with the X chromosome breakpoint at q26.1 was found with high-resolution trypsin-Giemsa banding. Somatic cell hybridization was used to separate the X chromosome derivative and the chromosome 20 derivative in order to position, with respect to the translocation breakpoint, several DNA loci that are linked to the Lowe syndrome locus (Xq24-q26). DXS10 and DXS53 were found to be distal to the breakpoint, whereas DXS37 and DXS42 were located proximal to it. These studies suggest that the OCRL locus lies in the region between these probes. The translocation chromosome originated from an unaffected male without a visible translocation, indicating that the most likely cause of OCRL in this patient is the de novo translocation that disrupted the OCRL locus.
 ...
PMID:Lowe oculocerebrorenal syndrome in a female with a balanced X;20 translocation: mapping of the X chromosome breakpoint. 189 26

The Lowe oculocerebrorenal syndrome (OCRL) is characterized by congenital cataract, mental retardation, and renal tubular dysfunction. We are using the approaches of linkage analysis, mapping with somatic cell hybrids, and long-range restriction mapping to determine the order of Xq24-q26 markers with respect to each other and to the OCRL locus. DXS42 and DXS100 are proximal to the translocation breakpoint in a female patient with OCRL and a de novo translocation t(X;3)(q25;q27). DXS10, DXS86, HPRT, and DXS177 are distal to the breakpoint. These flanking markers show tight linkage to the disease locus in 11 families segregating for OCRL. Results from field inversion gel analysis show that DXS86 and DXS10 share a 460-kb BssHII fragment. Multipoint analysis to determine the position of HPRT with respect to (DXS10,DXS86) suggests that HPRT is proximal to (DXS10,DXS86). We propose the following order for markers in Xq24-q26: Xcen-(DXS42,DXS37,DXS100)-OCRL-DXS53 -HPRT-[(DXS10,DXS86),DXS177]-Xqter. The identification of additional tightly linked flanking markers extends the number of markers available for use in genetic counseling and begins to define the physical map of the region containing the gene for OCRL.
 ...
PMID:Genetic and physical mapping of Xq24-q26 markers flanking the Lowe oculocerebrorenal syndrome. 208 1

Neurologic features of oculocerebrorenal (Lowe) syndrome include mental retardation, hypotonia, and areflexia. We performed a sural nerve biopsy, computerized tomography (CT) scan, and magnetic resonance imaging (MRI) scan on a 14-year-old boy with oculocerebrorenal syndrome with very mild renal disease. The nerve biopsy exhibited decreased number of myelinated fibers, normal myelination on remaining axons without redundant basal lamina, and no evidence of active degeneration or regeneration. MRI scan revealed diffuse and irregular foci of increased T2 signal with sparing of commissural fibers, pyramidal tracts, and cerebellar white matter. We conclude that both a peripheral axonopathy and a central demyelinating or gliotic process occurs in oculocerebrorenal syndrome in the absence of the severe renal disease that often complicates this disorder.
 ...
PMID:MRI findings and peripheral neuropathy in Lowe's syndrome. 283 62

The Lowe oculocerebrorenal syndrome (OCRL) is characterized by congenital cataract, mental retardation, and defective renal tubular function. A map assignment of OCRL to Xq24-q26 has been made previously by linkage analysis with DXS42 at Xq24-q26 (theta = 0, z = 5.09) and with DXS10 at Xq26 (theta = 0, z = 6.45). Two additional families were studied and three additional polymorphisms were identified at DXS42 by using a 35-kb sequence isolated with the probe detecting the original polymorphism at DXS42. With additional OCRL families made informative for DXS42, theta remained 0 with z = 6.63; and for DXS10 theta = 0.03 and z = 7.07. Evidence for placing OCRL at Xq25 also comes from a female with Lowe syndrome and an X;3 translocation. We have used the Xq25 breakpoint in this patient to determine the position of OCRL relative to the two linked markers. Each derivative chromosome was isolated away from its normal counterpart in somatic cell hybrids. DXS42 was mapped to the derivative chromosome X containing Xpterq25, and DXS10 was mapped to the derivative chromosome 3 containing Xq25-qter. The markers DXS10 and DXS42 therefore show tight linkage with OCRL in six families and flank the Xq25 breakpoint in a female patient with an X;3 translocation. Linkage analysis with flanking markers was used to assess OCRL carrier status in women at risk. Results, when compared with carrier determination by ophthalmologic examination, indicated that the slit-lamp exam can be a sensitive and specific method of carrier determination in many cases.
 ...
PMID:Tightly linked flanking markers for the Lowe oculocerebrorenal syndrome, with application to carrier assessment. 289 82

Parents who had previously given birth to a male with Lowe's syndrome were watched during a second pregnancy and a prenatal sex diagnosis was performed by amniocentesis. The fetus was a male and in proportion to the high rate of risk (50%), parents require to stop this second pregnancy. Instead of later renal failure and, of course, mental retardation, it was the histological features of the fetus eyes which permit to diagnose and exhibit both congenital cataract and irido-corneal angle dysgenesis.
 ...
PMID:[Antenatal diagnosis of Lowe's syndrome based on histologic tests of the fetal eyes]. 380 85

The oculocerebrorenal syndrome (OCRS), Lowe's syndrome, is an X-linked, recessive disease characterized by mental retardation, congenital corneal abnormalities and cataracts, growth failure, rickets, osseous abnormalities, renal dysfunction with periodic acidosis, hypotonia, and areflexia. Ultrastructural studies of skin biopsy specimens in three individuals with the disorder (aged 17, 9, and 8 years) revealed cytoplasmic, membrane-bound, electron-lucent vacuoles and some electron-dense membranous inclusion bodies in fibroblasts and Schwann cells, as well as axonal degeneration and vascular changes. Computed tomographic scans evidenced brain atrophy. Urinary excretion of glycosaminoglycans (GAG) was four to five times greater than in normal controls. The predominant urinary GAG was a low-sulfated chondroitin-4-sulfate; chondroitin-6-sulfate and heparan sulfate excretion levels were normal. A tenfold increase in urinary GAG excretion was found in one patient with oculocerebrorenal syndrome during periods of behavioral agitation. These findings suggest that the clinical stigmata of oculocerebrorenal syndrome may be related to a defect in GAG metabolism.
 ...
PMID:Ultrastructural, neurological, and glycosaminoglycan abnormalities in lowe's syndrome. 608 20

A thirty-three-year-old male with Lowe's syndrome had cataract; nystagmus, buphthalmos, prominent frontal bossing, growth and mental retardation, aminoaciduria, proteinuria, rickets, areflexia, genu valgum, piercing cry and head-banging being among the presenting features. The rickety changes improved over a period of years with the administration of vitamin D2. Pathological changes include: (1) tubular damage in the kidneys and hypertrophies of Bowman's capsules; (2) small brain with ventricular dilatation with thickened meninges, small corpus callosum, small size of pyramidal tracts and medial leminisci, neurofibrillary tangles in the pyramidal cells of the Ammon's horn and frontal lobe; (3) eye changes of buphthalmos, congenital cataracts and thickening of Descemet's membrane; (4) testicular atrophy--both testes showing peritubular fibrosis with an increase of fibrous tissue in the interstitial tissue. Azoospermia was present linked with poor development of spermatogonia and spermatocytes. The lumina of the seminiferous tubules were filled with foamy exudate.
 ...
PMID:Clinicopathological studies of oculo cerebrorenal syndrome of Lowe, Terrey and MacLachlan. 738 30

Oculocerebrorenal syndrome is an X-linked recessive disorder characterized by congenital ocular abnormalities, mental retardation, renal disease, and metabolic bone disease. We report a case of oculocerebrorenal syndrome and, using T1-, proton density-, and T2-weighted imaging sequences, are able to characterize two distinct white matter abnormalities: one lesion is punctate and has signal characteristics that parallel that of cerebrospinal fluid; a second lesion, found in association with the first, consists of patchy white matter abnormalities that are hypointense on T1-weighted images but hyperintense on proton density- and T2-weighted images.
 ...
PMID:MR findings in oculocerebrorenal syndrome. 784 33

The oculocerebrorenal syndrome of Lowe (OCRL; McKusick 309,000) is a rare X-linked disorder characterized by mental retardation, congenital cataracts, and Fanconi syndrome of the proximal renal tubules. We have carried out physical mapping of the OCRL1 gene and determined that it contains 24 exons occupying 58 kb. The gene, located in Xq25-26, is transcribed in a centromeric to telomeric direction. Primers have been developed that allow all coding exons and their intron/exon boundaries to be amplified from genomic DNA for mutation detection. Two tetranucleotide tandem repeat polymorphisms were characterized that immediately flank the OCRL1 gene and, together, are informative in over 90% of females. Variable splicing was seen in the OCRL1 transcript, involving a small 24-bp exon. These results should prove useful to medical and molecular geneticists studying mutations and providing DNA diagnostic services to families dealing with Lowe syndrome as well as to cell biologists interested in structure-function relationships for the OCRL1 protein.
 ...
PMID:Physical mapping and genomic structure of the Lowe syndrome gene OCRL1. 904 11


1 2 3 4 5 6 Next >>