Insulin resistance is associated with increased risk of atherosclerosis. Insulin receptor substrate-1 (IRS-1) plays a key role in tissue insulin sensitivity. A common mutation (G972R) of the IRS-1 gene has been shown to impair IRS-1 function, and it has been associated with reduced insulin sensitivity and lipid abnormalities. This led us to investigate the role of the G972R mutation in predispo...

Common variable immunodefi ciency (CVID) is a primary immunodeficiency involving a heterogeneous group of disorders characterized by recurrent bacterial infections and defi cient production of different classes of antibodies. The predisposing genetic factors associated with CVID remain unknown [1], although homozygous defects in ICOS or CD19 have been detected in a very small number of patients...

Methylation of cytosine to 5-methylcytosine (mC) is the most important epigenetic DNA alteration in eukaryotes. Cytosine methylation is involved in establishing a silenced chromatin stage through interaction with DNA-binding proteins and recruitment of histone deacetylases and other histone-modifying enzymes leading to chromatin remodeling. In this fashion, DNA methylation is connected with pro...

Individuals from 33 unrelated Australian families with optic atrophy were screened for 10 different single base alterations in mitochondrial DNA (mtDNA) associated with Leber hereditary optic neuropathy (LHON) using direct polymerase chain reaction amplification of blood spots collected on Guthrie cards. This method using blood spots allows easily accessible screening forLHON mtDNA mutations wi...

SIR, Familial Mediterranean fever (FMF) is a genetic disease with autosomal recessive transmission, occuring mainly in Middle-Eastern and eastern Mediterranean populations. Haplotype and mutation analysis has helped us trace the origins of this disease to the Fertile Crescent, located in the eastern Mediterranean [1]. Another rheumatological disease that is common in this area is Behçet’s disea...

Detecting rare mutant alleles in the background of wildtype DNA sequences and quantifying a specific DNA sequence in a clinical sample are two of the most challenging problems in DNA diagnostics. Successful approaches can expect important applications. For example, prenatal diagnosis of genetic disorders can be accomplished by invasive procedures such as amniocentesis, chorionic villus sampling...

The GAL7 gene of Saccharomyces cerevlsiae encodes Gal-l-P uridylyl transferase, the second enzyme of Leloir pathway for the galactose catabolism. We have determined the sequence of 1003 base pairs surrounding and upstream of the transcriptional initiation site of the GAL7 gene. The region sequenced also encompasses the 3' end of GAL10 gene. The 5 end of GAL7 mRNA was determined on the DNA seque...

Identification of polymorphism is the key for genetic mapping, diagnosis and marker-assisted selection. Restriction fragment-length polymorphisms (RFLPs) and short tandem repeats (STRs), also known as microsatellites, are commonly used genetic markers. Until discovery of STRs, RFLPs were used for genetic mapping, but bi-allelic polymorphism of RFLP limited its use as a marker. Although STRs are...

The discrimination mechanism between tRNA" and tRNA* was studied using various in vitro transcripts of E. coli tRNATyr variants. The insertion of only two nucleotides into the variable stem of tRNAv generates serine charging activity. The acceptor activities of some of the tRNA? mutants with insertions in the long variable arm were enhanced by changes in nucleotides at positions 9 and/or 20B, w...

Potato (Solanum tuberosum L.) and tomato (Lycopersicon esculentum) are members of the Solanaceae (nightshade family) and have the same basic chromosome number (x = 12). However, they cannot be cross-hybridized and, until now, it was unknown how conserved the gene order might be between these two species. We report herein the construction of a genetic linkage map of potato chromosomes based on g...