An aneugen is a substance that causes a daughter cell to have an abnormal number of chromosomes or

aneuploidy Aneuploidy is the presence of an abnormal number of chromosomes in a cell (biology), cell, for example a human somatic (biology), somatic cell having 45 or 47 chromosomes instead of the usual 46. It does not include a difference of one or more plo ...

. A substance's aneugenicity reflects its ability to induce aneuploidy. Unlike clastogens, aneugenic events do not damage the physical structure of the chromosome, but represent a deletion or insertion of an additional copy of a whole chromosome (i.e. with an intact

Centromere The centromere links a pair of sister chromatids together during cell division. This constricted region of chromosome connects the sister chromatids, creating a short arm (p) and a long arm (q) on the chromatids. During mitosis, spindle fiber ...

). Aneugens and clastogens can be differentiated via certain stains, using the technique of

Fluorescence in situ hybridization Fluorescence ''in situ'' hybridization (FISH) is a molecular cytogenetic technique that uses fluorescent probes that bind to only particular parts of a nucleic acid sequence with a high degree of sequence complementarity. It was developed by ...

. Males, if exposed to certain environmental and/or occupational chemical hazards may face an increased risk of

spermatozoa A spermatozoon (; also spelled spermatozoön; : spermatozoa; ) is a motile sperm cell (biology), cell produced by male animals relying on internal fertilization. A spermatozoon is a moving form of the ploidy, haploid cell (biology), cell that is ...

. Tobacco smoke contains chemicals that cause DNA damage (see Tobacco smoking#Health). Smoking also can induce

. In this study of men with a moderate smoking habit showed an association with increased chromosome 13 disomy in spermatozoa by 3-fold and YY disomy by 2-fold. Occupational exposure to benzene is associated with a 2.8-fold increase of XX disomy and a 2.6-fold increase of YY disomy in spermatozoa.

Pesticide Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all p ...

s are released to the environment in large quantities so that most individuals have some degree of exposure. The

insecticide Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...

s fenvalerate and

carbaryl Carbaryl (1-naphthyl methylcarbamate) is a chemical in the carbamate family used chiefly as an insecticide. It is a white crystalline solid previously sold under the brand name Sevin, which was a trademark of the Bayer Company. Union Carbide disc ...

have been reported to increase spermatozoa aneuploidy. Occupational exposure of pesticide factory workers to fenvalerate is associated with increased spermatozoa DNA damage. Exposure to fenvalerate raised sex chromosome disomy 1.9-fold and disomy of chromosome 18 by 2.6-fold (Xia et al., 2004). Exposure of male workers to carbaryl increased DNA fragmentation in spermatozoa, and also increased sex chromosome disomy by 1.7-fold and chromosome 18 disomy by 2.2-fold. Humans are exposed to

perfluorinated compound A perfluorinated compound (PFC) or perfluoro compound is an Organofluorine chemistry, organofluorine compound that lacks C-H bonds. Many perfluorinated compounds have properties that are quite different from their C-H containing analogues. Common ...

s (PFCs) in many commercial products. Men contaminated with PFCs in whole blood or seminal plasma have spermatozoa with increased levels of DNA fragmentation and chromosomal aneuploidies.

References

{{Genotoxicity Carcinogenesis

See also

References