title: A possible association of a human tektin-t gene mutation (A229V) with isolated non-syndromic asthenozoospermia: case report.
abstract: Asthenozoospermia (AZS), characterized by grade A + B sperm motility (as in World Health Organization Guidelines) < or =50% or A <25% in fresh ejaculate, may exist as an isolated disorder, in combination with other sperm anomalies or as part of syndromic association. The majority of syndromic patients can be ascribed to mutations in dynein genes, while, to date, no genes have been described to be associated in humans with non-syndromic, isolated AZS. An interesting family of axonemal proteins, the tektins, has been recently identified in various mammals and they are thought to play a fundamental role in ciliary movement. Recently, the human tektin-t (or h-tekB1 or Tektin-2) gene has been cloned, showing specific expression in flagella of mature sperm. We report the screening of tektin-t gene in 90 isolated non-syndromic AZS patients. We found a heterozygous mutation (A229V) in one patient. Ultrastructural analysis showed anomalies in > or =80% of examined spermatozoa involving axoneme microtubules and mitochondria. Moreover, the viability and mitochondrial function of sperm were altered in the patient with the A229V mutation. This is the first description of human pathology linked to a tektin-family gene, since only murine models are available for these genes.
authors.affiliation: Department of Histology, Microbiology and Medical Biotechnologies, Centre for Male Gamete Cryopreservation, University of Padova, Via Gabelli 63, 35121 Padova, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Zuccarello
authors.forename: Alberto
authors.initials: A
authors.lastname: Ferlin
authors.forename: Andrea
authors.initials: A
authors.lastname: Garolla
authors.forename: Mauro A
authors.initials: MA
authors.lastname: Pati
authors.forename: Afra
authors.initials: A
authors.lastname: Moretti
authors.forename: Carla
authors.initials: C
authors.lastname: Cazzadore
authors.forename: Sandro
authors.initials: S
authors.lastname: Francavilla
authors.forename: Carlo
authors.initials: C
authors.lastname: Foresta
mesh_terms: D000328:Adult; D053627:Asthenozoospermia / Q000235:genetics*; D006801:Humans; D008297:Male; D008868:Microtubule Proteins / Q000235:genetics*; D009154:Mutation; D016133:Polymerase Chain Reaction; D013094:Spermatozoa
chemical_list: D008868:Microtubule Proteins; C044103:tektins