Biomaterial Database

Detection and differentiation of causative fungi of onychomycosis using PCR amplification and restriction enzyme analysis. 1998

S C Baek, and H J Chae, and D Houh, and D G Byun, and B K Cho

Department of Dermatology, School of Medicine, The Catholic University of Korea, Seoul, South Korea.

BACKGROUND Onychomycosis, a fungal nail infection, has become one of the most important dermatophytoses. Unfortunately, a predictably successful diagnostic approach to onychomycosis does not yet exist. OBJECTIVE The purpose of this study was to develop a deoxyribonucleic acid (DNA)-based diagnostic method to improve the sensitivity and specificity of the detection and differentiation of the pathogenic fungi of onychomycosis. METHODS We attempted to detect fungi in the nail using polymerase chain reaction (PCR) primer systems that were designed in conserved sequences of the small ribosomal subunit 18S-rRNA genes shared by most fungi, and differentiated between species by restriction enzyme analysis of the amplified product. RESULTS Fragments of the gene coding for 18S-rRNA were amplified successfully from medically important fungi species, but not from normal nails. Restriction fragment length polymorphism patterns using HaeIII endonuclease were sufficiently different to allow the recognition of individual species. CONCLUSIONS The PCR-restriction enzyme analysis method appears to be a more sensitive detection and identification technique for onychomycosis than conventional methods, and has considerable diagnostic value.

UI	MeSH Term	Description	Entries
D009262	Nails	The thin, horny plates that cover the dorsal surfaces of the distal phalanges of the fingers and toes of primates.	Fingernails,Toenails,Fingernail,Nail,Toenail
D002176	Candida albicans	A unicellular budding fungus which is the principal pathogenic species causing CANDIDIASIS (moniliasis).	Candida albicans var. stellatoidea,Candida stellatoidea,Dematium albicans,Monilia albicans,Myceloblastanon albicans,Mycotorula albicans,Parasaccharomyces albicans,Procandida albicans,Procandida stellatoidea,Saccharomyces albicans,Syringospora albicans
D003883	Arthrodermataceae	A family of ascomycetous fungi, order Onygenales, characterized by smooth ascospores. Genera in the family include Arthroderma, Keratinomyces, and Ctenomyces. Several well-known anamorphic forms are parasitic upon the skin.	Arthroderma,Ctenomyces,Dermatophytes,Keratinomyces,Cutaneous Fungi,Cutaneous Fungus,Dermatomyces,Nannizzia,Arthrodermas,Ctenomyce,Dermatomyce,Dermatophyte,Fungi, Cutaneous,Fungus, Cutaneous,Keratinomyce,Nannizzias
D004262	DNA Restriction Enzymes	Enzymes that are part of the restriction-modification systems. They catalyze the endonucleolytic cleavage of DNA sequences which lack the species-specific methylation pattern in the host cell's DNA. Cleavage yields random or specific double-stranded fragments with terminal 5'-phosphates. The function of restriction enzymes is to destroy any foreign DNA that invades the host cell. Most have been studied in bacterial systems, but a few have been found in eukaryotic organisms. They are also used as tools for the systematic dissection and mapping of chromosomes, in the determination of base sequences of DNAs, and have made it possible to splice and recombine genes from one organism into the genome of another. EC 3.21.1.	Restriction Endonucleases,DNA Restriction Enzyme,Restriction Endonuclease,Endonuclease, Restriction,Endonucleases, Restriction,Enzymes, DNA Restriction,Restriction Enzyme, DNA,Restriction Enzymes, DNA
D004271	DNA, Fungal	Deoxyribonucleic acid that makes up the genetic material of fungi.	Fungal DNA
D005784	Gene Amplification	A selective increase in the number of copies of a gene coding for a specific protein without a proportional increase in other genes. It occurs naturally via the excision of a copy of the repeating sequence from the chromosome and its extrachromosomal replication in a plasmid, or via the production of an RNA transcript of the entire repeating sequence of ribosomal RNA followed by the reverse transcription of the molecule to produce an additional copy of the original DNA sequence. Laboratory techniques have been introduced for inducing disproportional replication by unequal crossing over, uptake of DNA from lysed cells, or generation of extrachromosomal sequences from rolling circle replication.	Amplification, Gene
D005800	Genes, Fungal	The functional hereditary units of FUNGI.	Fungal Genes,Fungal Gene,Gene, Fungal
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012337	RNA, Ribosomal, 18S	Constituent of the 40S subunit of eukaryotic ribosomes. 18S rRNA is involved in the initiation of polypeptide synthesis in eukaryotes.	18S Ribosomal RNA,18S RRNA,RNA, 18S Ribosomal,Ribosomal RNA, 18S
D014009	Onychomycosis	A fungal infection of the nail, usually caused by DERMATOPHYTES; YEASTS; or nondermatophyte MOLDS.	Nail Fungus,Tinea Unguium,Fungus, Nail,Onychomycoses