Disease relevance of IDS

• Mutations causing IDS deficiency in humans result in the lysosomal storage of these glycosaminoglycans and Hunter syndrome, an X chromosome-linked disease [1].
• Mucopolysaccharidosis type II (MPS II, Hunter syndrome) is an X-chromosomal storage disorder due to deficiency of the lysosomal enzyme iduronate-2-sulfatase (IDS) [2].
• We examined the antibody responses of Lyme disease patients to IDS lysate components in order to further understand the pathogenesis of this disease [3].
• A spirochete (IDS) isolated from Ixodes dammini ticks has been implicated as the etiologic agent of Lyme disease [3].
• Moloney murine leukemia virus-derived retroviral vectors were constructed by inserting the IDS cDNA under transcriptional regulation of the long terminal repeat (LTR) (in vector L2SN) or the cytomegalovirus (CMV) early promoter (vector LNC2) [4].

Psychiatry related information on IDS

• During the critical period for SIDS, infant sleep begins to coalesce from a series of naps to more prolonged night time sleep periods that last up to 8 hours [5].
• Nevertheless, multichannel recordings in the hospital have provided a useful tool in the initial evaluation of many infants with infant apnea, and, for SIDS research, they have been useful for evaluating the complex autonomic control mechanisms during sleep and wakefulness [6].
• SIDS, seizures or 'sophageal reflux? Another manifestation of Munchausen syndrome by proxy [7].
• Postnatal depression and SIDS [8].
• Risk factors for SIDS. Results of the National Institute of Child Health and Human Development SIDS Cooperative Epidemiological Study [9].

High impact information on IDS

• The levels of biotin in the livers of infants who had died of sudden infant death syndrom (SIDS; cot death) were significantly lower than those in livers of infants of similar age, who had died of explicable causes [10].
• These findings support an association of biotin with SIDS [10].
• Smoking, tobacco exposure through breast milk, and SIDS [11].
• Increased immune response in upper respiratory and digestive tracts in SIDS [12].
• While the distribution of gene rearrangements (deletions, insertions, and duplications) of <20 bp seems to be random over the IDS gene, the analysis of a total of 101 point mutations lying within the coding region shows that they tend to be more frequent in exons III, VIII, and IX [2].

Chemical compound and disease context of IDS

• Hunter disease (mucopolysaccharidosis type II or MPS II) is an X-linked recessive disorder caused by the deficiency of the lysosomal enzyme iduronate-2-sulfatase (IDS) (E.C.3.1.6.13.) involved in the catabolism of mucopolysaccharides dermatan sulfate and heparan sulfate [13].
• Maternal smoking correlates highly with parturitional/neonatal death including SIDS; nicotine exposure of fetal rats reproduces the increased mortality when animals are tested postnatally with hypoxia [14].

Biological context of IDS

• The IDS sequence has strong sequence homology with other sulfatases (such as sea urchin arylsulfatase, human arylsulfatases A, B, and C, and human glucosamine 6-sulfatase), suggesting that the sulfatases comprise an evolutionarily related family of genes that arose by gene duplication and divergent evolution [1].
• Patients with complete deletion of the IDS locus often have atypical phenotypes including ptosis, obstructive sleep apnoea, and the occurrence of seizures [15].
• We have used exon to exon and vectorette PCR to identify 9 exons within the IDS gene and to characterise the surrounding intron sequences [16].
• We report characterization of 28 cosmids around the IDS locus in Xq28 [17].
• Genomic DNA and cDNA from fibroblasts from nine unrelated German patients with X-linked iduronate-2-sulfatase (IDS) deficiency showing variable clinical manifestation were screened for point mutations and small structural aberrations [18].

Anatomical context of IDS

• A minor population of the IDS message was processed by using this cryptic splice site; however, no correctly spliced message was detected in leukocytes from this patient [19].
• Iduronate-2-sulfatase (IDS) cDNA from fibroblasts of nine patients with Hunter syndrome (mucopolysaccharidosis type II) was screened for mutations using single strand conformation polymorphism analysis [20].
• Iduronate-2-sulfatase (IDS) is involved in the degradation of heparan sulfate and dermatan sulfate in the lysosomes, and a deficiency in this enzyme results in Hunter syndrome [21].
• By following the segregation of a restriction fragment length polymorphism at the IDS locus in the patient's family, our data suggest that the deletion occurred in the germ cells of the patient's grandfather [22].
• These results demonstrated retroviral-mediated IDS gene transfer into lymphoid cells and the ability of such cells to provide recombinant enzyme for intercellular metabolic cross-correction [23].

Associations of IDS with chemical compounds

• Iduronate 2-sulfatase (IDS, EC 3.1.6.13) is required for the lysosomal degradation of heparan sulfate and dermatan sulfate [1].
• The disease is caused by the inability to degrade dermatan sulphate and heparan sulphate due to mutations in the iduronate-2-sulphatase gene (IDS) [24].
• To gain insight into the relationship between methylation status and CpG hot spot mutations, we investigated patterns of cytosine methylation in the entire IDS gene, except for introns 4-8 [25].
• Furthermore, endocytosis of the transduced IDS did occur via the mannose-6-phosphate (M6P) receptor [26].
• An aliquot (5 x 10(7)) of PBL apheresis product was precultured in a gas-permeable culture bag or a bioreactor, and then transduced with a retroviral vector L2SN containing the iduronate-2-sulfatase (IDS) and neomycin resistance genes [27].

Other interactions of IDS

• Deletions of the IDS gene can include a conserved locus that is tightly linked to FRAXA, suggesting that deletion of nearby genes may contribute to the variable clinical severity noted in Hunter syndrome [28].
• Prediction of the clinical phenotype from the identified genotype was difficult in some families, and further studies using reverse transcription polymerase chain reaction are needed to confirm the predicted effects on the IDS mRNA suggested by genomic analysis [29].
• Mucopolysaccharidosis type I (i.e., Hurler, Hurler-Scheie, and Scheie syndromes) and type II (i.e., Hunter syndrome) are lysosomal storage disorders resulting from alpha-L-iduronidase (IDUA) deficiency and iduronate-2-sulfatase (IDS) deficiency, respectively [30].
• The frequency of the IDS polymorphism is 46% in Caucasian females and 39% in African-American females; in combination with G6PD and p55, 76% of Caucasian females and 62% of African-American females are informative for these assays [31].
• Southern analysis of DNA extracted from somatic cell hybrids containing only the mutant X chromosome showed deletion of the Xq27.3-q28 loci: DXS297 (VK23AC), DXS293 (VK16), FRAXA (pfxa3), DXS296 (VK21A), and the 3' end of the iduronatesulfatase (IDS) gene [32].

Analytical, diagnostic and therapeutic context of IDS

• PCR amplicons representing the IDS cDNA were sequenced with an automatic instrument, and output was analyzed by computer-assisted interpretation of tracings, using Staden programs on a Sun computer [19].
• We sequenced genomic DNA and RT-PCR products in the iduronate sulfatase (IDS) gene in 6 unrelated patients with Hunter syndrome to assess genotype/phenotype relationships and offer carrier testing where required [33].
• This study has demonstrated a procedure capable of detecting all types of mutation that affect the function of the IDS protein and should enable direct carrier and prenatal diagnosis for Hunter syndrome families [34].
• In contrast to the findings with Lyme disease sera, sera from controls showed little reactivity with IDS components in either the western blots or a derivative solid-phase radioimmunoassay [3].
• These studies of retrovirus-mediated expression and metabolic correction, finding near-normal levels of IDS in cultured PBLMPS and metabolic correction, demonstrate the potential for treatment of mild, nonneuropathic Hunter syndrome by means of ex vivo lymphocyte gene therapy [4].

References