Gene polymorphisms/mutations relevant to abnormal spermatogenesis.
Despite the identification of an increasing number of candidate genes involved in spermatogenesis, the armamentarium of diagnostic genetic tests in male infertility remains extremely limited. A number of new causative mutations have been reported for hypogonadotrophic hypogonadism but still the genetic diagnosis in this pathological condition is made only in about 20% of cases. The sole molecular genetic test that is routinely proposed in severe spermatogenic disturbances is screening for Yq microdeletion. The search for causative mutations in the Y chromosome, and in autosomal and X-linked genes, has mostly been unsuccessful. The paucity of gene mutations raises questions about the appropriateness of the currently used screening approaches. Among the proposed genetic risk factors, gr/gr deletion of the Y chromosome seems to be the most promising polymorphism. Other polymorphisms are awaiting further confirmation, whereas for some (POLG, DAZL, USP26, FSHR) a lack of association with abnormal spermatogenesis has now been ascertained. It is likely that some polymorphisms lead to testicular dysfunction only when in association with a specific genetic background or with environmental factors. Future large-scale studies with stringent study design may provide a more efficient way to identify clinically relevant genetic factors of male infertility.
Nuti
Francesca
F
Andrology Unit, Department of Clinical Physiopathology, Viale Pieraccini, 6, 50139 Florence, Italy.
Krausz
Csilla
C
D000818:Animals; D005796:Genes / Q000502:physiology; D056426:Genetic Loci; D020022:Genetic Predisposition to Disease; D006062:Gonadotropins / Q000172:deficiency; D006801:Humans; D007248:Infertility, Male / Q000235:genetics*; D008297:Male; D009154:Mutation / Q000502:physiology; D020641:Polymorphism, Single Nucleotide; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics; D029589:Seminal Plasma Proteins / Q000235:genetics; D013091:Spermatogenesis / Q000235:genetics*; D014998:Y Chromosome / Q000235:genetics
D006062:Gonadotropins; D018160:Receptors, Cytoplasmic and Nuclear; D029589:Seminal Plasma Proteins