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International Journal of Dermatology Apr 1990
Topics: Bloom Syndrome; Cohort Studies; Humans; New York City; Registries
PubMed: 2335424
DOI: 10.1111/j.1365-4362.1990.tb03815.x -
Indian Journal of Experimental Biology Apr 1996Bloom syndrome (BS), an autosomal recessive genetic disorder, is an instructive model to explore variety of questions in "deregulation of normal cell functioning". Most... (Review)
Review
Bloom syndrome (BS), an autosomal recessive genetic disorder, is an instructive model to explore variety of questions in "deregulation of normal cell functioning". Most of the BS patients are homozygous for mutant BLM gene and depict high sister chromatid exchanges (SCEs) in almost all the cells. However, a few possess cells with dimorphic SCE phenotype. A majority of patients with dimorphic SCE phenotype have been suggested to be compound heterozygotes, inheriting two different mutations in the BLM locus from each parent. An intragenic somatic recombination event in a precursor stem cell in such patients is envisaged to give rise to a population of cells with functionally wild-type (BLM) gene and normal SCE phenotype. Adopting unique dual approaches of positional mapping through "homozygosity by descent" and "somatic crossover point mapping", a candidate for BLM has been identified and localized to a 250 Kb interval between polymorphic loci, DI5S1108 and D15127. The sequence has been found to encode a 1417 amino acid peptide with homology to the RecQ helicases, a sub-family of DExH box-containing DNA and RNA helicases. The presence of chain terminating mutations in the 'candidate' gene in BS patients has suggested it to be the BLM gene. Apparantly the proposed gene product does not seem to provide answer for a variety of clinical, biochemical and experimental observations made in BS or BS cells till date. Our recent observation of a significant decrease in the activity of pyruvate kinase in three BS B-lymphoblastoid cell lines when compared to a similar cell line established from a normal healthy subject presents with another possible candidate to elucidate the defects in BS. Experiments using okadaic acid, a phosphatase-2a/1 inhibitor, have depicted in our study that many of the clinical features characteristic of BS, not easily explanable by the recently proposed BLM gene, can be explained by the deficiency in the PK alone and/or PP2a/PP1 activity.
Topics: Bloom Syndrome; Chromosome Mapping; Genes, Recessive; Humans
PubMed: 8698416
DOI: No ID Found -
Ryoikibetsu Shokogun Shirizu 2000
Review
Topics: Adenosine Triphosphatases; Bloom Syndrome; DNA Helicases; DNA Repair; Disease Susceptibility; Humans; Infections; Mutation; Neoplasms; RecQ Helicases
PubMed: 11212711
DOI: No ID Found -
Ryoikibetsu Shokogun Shirizu 2001
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Ryoikibetsu Shokogun Shirizu 2000
Review
Topics: Adenosine Triphosphatases; Bloom Syndrome; Chromosomes, Human, Pair 15; DNA Helicases; DNA Repair; Diagnosis, Differential; Humans; Prognosis; RecQ Helicases; Sister Chromatid Exchange
PubMed: 11057173
DOI: No ID Found -
Ryoikibetsu Shokogun Shirizu 1998
Review
Topics: Bloom Syndrome; Chromosome Aberrations; Female; Humans; Male; Prognosis; Sister Chromatid Exchange
PubMed: 9833485
DOI: No ID Found -
Cold Spring Harbor Molecular Case... Apr 2021Bloom syndrome is a rare autosomal recessive disorder with less than 300 cases reported in the literature. Bloom syndrome is characterized by chromosome instability,...
Bloom syndrome is a rare autosomal recessive disorder with less than 300 cases reported in the literature. Bloom syndrome is characterized by chromosome instability, physical stigmata, growth deficiency, immunodeficiency, and a predisposition to cancer, most commonly leukemias, although solid tumors are reported as well. Bloom syndrome occurs in multiple ethnic groups with a higher incidence in persons of Ashkenazi Jewish origin. Few patients of Hispanic ethnicity have been reported. We report here a Mexican American family with a pathogenic variant, c.2506_2507delAG, previously reported in a single patient from Mexico. In this family of four siblings, three have phenotypic features of Bloom syndrome, and gene mutation was homozygous in these affected individuals. Our proband developed a rhabdomyosarcoma. Analysis of surrounding markers in the germline DNA revealed a common haplotype, suggesting a previously unrecognized founder mutation in the Hispanic population of Mexican origin.
Topics: Alleles; Bloom Syndrome; Child, Preschool; Genetic Predisposition to Disease; Homozygote; Humans; Male; Mexican Americans; Mexico; Mutation; Pedigree; Polymorphism, Single Nucleotide; RecQ Helicases; Rhabdomyosarcoma
PubMed: 33832920
DOI: 10.1101/mcs.a005751 -
BMJ Case Reports Oct 2020We report a case of a 5-year-old boy presenting to us with short stature. He was born of consanguineous parentage and was small for gestational age. He had severe short...
We report a case of a 5-year-old boy presenting to us with short stature. He was born of consanguineous parentage and was small for gestational age. He had severe short stature, with height Z score of -6.2 SD Score, markedly delayed skeletal age, low level of insulin-like growth factor 1, unstimulated growth hormone and hypoplastic anterior pituitary gland on MRI. He was advised growth hormone (GH) replacement at 2 years of age, but he did not receive it . Later on, he developed photosensitive telangiectatic lesions over face and required multiple hospital admissions for recurrent systemic infections. Genetic analysis confirmed the diagnosis of Bloom's syndrome. The present case report illustrates the need for high vigilance for conditions like Bloom's syndrome in growth hormone deficiency (GHD), in whom GH treatment could potentially be harmful. Bloom's syndrome with GHD is an exceedingly rare association.
Topics: Abnormalities, Multiple; Biomarkers; Bloom Syndrome; Brain; Child, Preschool; Dwarfism, Pituitary; Human Growth Hormone; Humans; Magnetic Resonance Imaging; Male; Rare Diseases
PubMed: 33122222
DOI: 10.1136/bcr-2020-235238 -
Frontiers in Endocrinology 2021Bloom syndrome (BS) is a rare autosomal recessive disorder that causes several endocrine abnormalities. So far, only one BS pedigree, without diabetes, has been reported...
Bloom syndrome (BS) is a rare autosomal recessive disorder that causes several endocrine abnormalities. So far, only one BS pedigree, without diabetes, has been reported in the Chinese population. We presented the first case of BS with diabetes in the Chinese population and explored the clinical spectrum associated with endocrine. Possible molecular mechanisms were also investigated. Our study indicated that BS may be one rare cause of diabetes in the Chinese population. We also found a new pathogenic sequence variant in (BLM RecQ like helicase gene)(NM_000057.4) c.692T>G, which may expand the spectrum of variants.
Topics: Bloom Syndrome; Diabetes Mellitus, Type 1; Humans; Male; Mutation; RecQ Helicases; Young Adult
PubMed: 34177791
DOI: 10.3389/fendo.2021.524242 -
Clinical Dysmorphology Apr 2023
Topics: Child; Humans; Bloom Syndrome; Lung
PubMed: 36876347
DOI: 10.1097/MCD.0000000000000448