Quantification by flow cytometry of chromosome-17 deletions in Smith-Magenis syndrome patients.

We have used bivariate flow karyotyping to quantify the deletions involving chromosome 17 in sixteen patients with Smith-Magenis syndrome (SMS). The fluorescence intensities of mitotic chromosomes stained with Hoechst 33258 and chromomycin were quantified in a dual-beam flow cytometer. For each patient, the position of the peak representing the deleted chromosome 17 was compared to those of the normal homologs of an unaffected parent.

Cloning and comparative mapping of a gene from the commonly deleted region of DiGeorge and Velocardiofacial syndromes conserved in C. elegans.

We have identified and cloned a gene, ES2, encoding a putative 476 amino acid protein with a predicted Mr of 52,568. The gene is localized within the DiGeorge/Velocardiofacial syndrome locus on 22q11.2 and is deleted in all the patients in which a deletion within 22q11 could be demonstrated, with the exception of one patient.

Duplication of a gene-rich cluster between 16p11.1 and Xq28: a novel pericentromeric-directed mechanism for paralogous genome evolution.

We have identified a 26.5 kb gene-rich duplication shared by human Xq28 and 16p11.1.

Identification of a novel transcript disrupted by a balanced translocation associated with DiGeorge syndrome.

Most cases of DiGeorge syndrome (DGS) and related abnormalities are associated with deletions within 22q11. Shortest region of deletion overlap (SRO) mapping previously identified a critical region (the DGCR) of 500 kb, which was presumed to contain a gene or genes of major effect in the haploinsufficiency syndromes. The DGCR also contains sequences disrupted by a balanced translocation that is associated with DGS--the ADU breakpoint.

Molecular analyses of 17p11.2 deletions in 62 Smith-Magenis syndrome patients.

Smith-Magenis syndrome (SMS) is a clinically recognizable, multiple congenital anomalies/mental retardation syndrome caused by an interstitial deletion involving band p11.2 of chromosome 17. Toward the molecular definition of the interval defining this microdeletion syndrome, 62 unrelated SMS patients in conjunction with 70 available unaffected parents were molecularly analyzed with respect to the presence or absence of 14 loci in the proximal region of the short arm of chromosome 17.

A transcription map in the CATCH22 critical region: identification, mapping, and ordering of four novel transcripts expressed in heart.

The acronym CATCH22 is used to indicate collectively a group of related phenotypes, namely velocardiofacial syndrome (VCFS), DiGeorge anomaly (DGA), and conotruncal anomaly face, which are associated with deletions within 22q11.2 in the great majority of patients. A deletion map has allowed us to delimit a smallest region of deletion overlap, considerably smaller than the commonly deleted region.

Haploinsufficiency of cytosolic serine hydroxymethyltransferase in the Smith-Magenis syndrome.

Folate-dependent one-carbon metabolism is critical for the synthesis of numerous cellular constituents required for cell growth, and serine hydroxymethyltransferase (SHMT) is central to this process. Our studies reveal that the gene for cytosolic SHMT (cSHMT) maps to the critical interval for Smith-Magenis syndrome (SMS) on chromosome 17p11.2.

LIS2, gene and pseudogene, homologous to LIS1 (lissencephaly 1), located on the short and long arms of chromosome 2.

We report here the isolation of a novel cDNA, designated LIS2, that maps to chromosome 2p11.2 by in situ hybridization and demonstrates extremely high sequence similarity to the recently identified LIS1 gene involved in Miller-Dieker lissencephaly at 17p13.3.

Smith-Magenis syndrome deletion: a case with equivocal cytogenetic findings resolved by fluorescence in situ hybridization.

The availability of markers for the 17p11.2 region has enabled the diagnosis of Smith-Magenis syndrome (SMS) by fluorescence in situ hybridization (FISH). SMS is typically associated with a discernible deletion of band 17p11.

Diagnosis of X-linked adrenal hypoplasia congenita by mutation analysis of the DAX1 gene.

Objective: To develop a rapid diagnostic approach to individuals with the X-linked cytomegalic form of adrenal hypoplasia congenita (AHC) and hypogonadotropic hypogonadism (HH) due to mutations in DAX1, a new member of the nuclear hormone receptor gene superfamily.

Design: Molecular genetic diagnostic investigations of individuals with AHC and their relatives included polymerase chain reaction amplification of DAX1 for identification of intragenic mutations and fluorescence in situ hybridization with a cosmid containing the DAX1 gene for evaluation of larger deletions.

Participants: Families that had males affected with AHC were evaluated for mutations involving the DAX1 gene.

Rapid molecular cytogenetic analysis of X-chromosomal microdeletions: fluorescence in situ hybridization (FISH) for complex glycerol kinase deficiency.

Diagnosis of X-chromosomal microdeletions has relied upon the traditional methods of Southern blotting and DNA amplification, with carrier identification requiring time-consuming and unreliable dosage calculations. In this report, we describe rapid molecular cytogenetic identification of deleted DNA in affected males with the Xp21 contiguous gene syndrome (complex glycerol kinase deficiency, CGKD) and female carriers for this disorder. CGKD deletions involve the genes for glycerol kinase, Duchenne muscular dystrophy, and/or adrenal hypoplasia congenita.

Velo-cardio-facial syndrome: frequency and extent of 22q11 deletions.

Velo-cardio-facial (VCFS) or Shprintzen syndrome is associated with deletions in a region of chromosome 22q11.2 also deleted in DiGeorge anomaly and some forms of congenital heart disease. Due to the variability of phenotype, the evaluation of the incidence of deletions has been hampered by uncertainty of diagnosis.

A human homologue of the Drosophila polarity gene frizzled has been identified and mapped to 17q21.1.

The frizzled (fz) locus in Drosophila is required for the transmission of polarity signals across the plasma membrane in epidermal cells, as well as to their neighboring cells in the developing wing. The identification of a tissue polarity gene from the fz locus in Drosophila melanogaster has been reported. The fz gene encodes a protein (Fz) with seven putative transmembrane domains, which was suggested to function as a G-protein-coupled receptor.

Human acetyl-CoA carboxylase: characterization, molecular cloning, and evidence for two isoforms.

We have cloned and sequenced the cDNA coding for human HepG2 acetyl-CoA carboxylase (ACC; EC 6.4.1.

De novo tandem duplication of chromosome segment 22q11-q12: clinical, cytogenetic, and molecular characterization.

We report on a case of duplication of the segment 22q11-q12 due to a de novo duplication. Molecular cytogenetics studies demonstrated this to be a tandem duplication, flanked proximally by the marker D22Z4, a centromeric alpha satellite DNA repeat, and distally by D22S260, an anonymous DNA marker proximal to the Ewing sarcoma breakpoint. The segment includes the regions responsible for the "cat-eye," Di George, and velo-cardio-facial syndromes and extends distal to the breakpoint cluster region (BCR).

The gene for a human microfibril-associated glycoprotein is commonly deleted in Smith-Magenis syndrome patients.

Smith-Magenis syndrome (SMS) is a clinically recognizable multiple congenital anomaly/mental retardation syndrome associated with deletion of chromosome 17p11.2. Here we report the identification of a novel gene encoding a human microfibril-associated glycoprotein (MFAP4), which has been mapped to the SMS region.

[43 cases of primary empty sella syndrome: a case series].

Primary empty sella syndrome (ESS) is an anatomo-radiological picture characterized by the presence of an arachnoid herniation filled with liquor that compresses the pituitary against the sellar wall. ESS occurs particularly in obese, hypertensive, cephalalgic women. It is often asymptomatic but may be associated with ophthalmologic, neurologic and non-characterizing endocrine disorders.

Submicroscopic deletions at 22q11.2: variability of the clinical picture and delineation of a commonly deleted region.

DiGeorge anomaly (DGA) and velo-cardiofacial syndrome (VCFS) are frequently associated with monosomy of chromosome region 22q11. Most patients have a submicroscopic deletion, recently estimated to be at least 1-2 Mb. It is not clear whether individuals who present with only some of the features of these conditions have the deletion, and if so, whether the size of the deletion varies from those with more classic phenotypes.

Cloning and mapping of the mouse alpha 7-neuronal nicotinic acetylcholine receptor.

We report the isolation of cDNA clones for the mouse alpha 7 neuronal nicotinic acetylcholine receptor subunit (gene symbol Acra7), the only nicotinic receptor subunit known to bind alpha-bungarotoxin in mammalian brain. This gene may have relevance to nicotine sensitivity and to some electrophysiologic findings in schizophrenia. The mouse alpha 7 subunit gene encodes a protein of 502 amino acids with substantial identity to the rat (99.