XYY syndrome is an aneuploidyAneuploidy is a change in the number of chromosomes that can lead to a chromosomal disorder. The most recognized forms of aneuploidy are the trisomy diseases of Down syndrome and Edwards syndrome. Trisomy may not necessarily be present in all cells in an individual. It may be detected in just a specific tissue or within different cells in a tissue. When the presence of chromosomal abnormalities ...aneuploidy (specifically a trisomy) of the sex chromosomesA sex-determination system is a biological system that determines the development of sexual characteristics in an organism. Most sexual organisms have two sexes. In many cases, sex determination is genetic: males and females have different alleles or even different ...sex chromosomes in which a humanHumans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin: "wise man" or "knowing man") in the family Hominidae (the great apes). Humans have a highly developed brain capable of abstract reasoning, language, and introspection. This mental capability, combined with an erect body carriage that frees their upper limbs for manipulating objects, has allowed humans to make far greater use of tools than any other species. Humans originated in Africa about 200,000 years ago, but they now inhabit ...human maleMale (♂) refers to the sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete, or ovum, in the process of fertilisation. A male cannot reproduce sexually without access to at least one ovum from a female, but some organisms can reproduce both sexually and asexually. Not all species share a common sex-determination ...male receives an extra Y chromosomeThe Y chromosome is one of the sex-determining chromosomes in humans and most other mammals (the other is the X chromosome). In mammals, it contains the gene SRY, which triggers testis development, thus determining sex.Y chromosome, producing a 47,XYY karyotypeA karyotype is the observed characteristics (number, type, shape etc) of the chromosomes of an individual or species. In normal diploid organisms, autosomal chromosomes are present in two identical copies, although polyploid cells have multiple copies of chromosomes and haploid cells have single copies. The chromosomes are arranged and displayed (often ...karyotype.
Some medical geneticists question whether the term "syndromeIn medicine and psychology, the term syndrome refers to the association of several clinically recognizable features, signs (discovered by a physician), symptoms (reported by the patient), phenomena or characteristics which often occur together, so that the presence of one feature alerts the physician to the presence of the others. In recent decades the term has been used outside of medicine to refer to a combination ...syndrome" is appropriate for this condition because its phenotypeThe phenotype (from Ancient Greek: pheno- "appearing, seeming" and -type "sort, kind") of an individual organism describes one of its traits or characteristics that is measurable and that is expressed in only a subset of the individuals within that population Encyclopedia of Genetics, Ed. Sydney Brenner and Jeffrey H. Miller. San Diego: Academic Press, 2002.. Examples include "blue eyes", or "aggressive behavior". Some phenotypes are controlled entirely by the individual's genes. Others are controlled by genes but are significantly ...phenotype is normal and the vast majority (an estimated 97% in the UK) of 47,XYY males do not know their karyotypeA karyotype is the observed characteristics (number, type, shape etc) of the chromosomes of an individual or species. In normal diploid organisms, autosomal chromosomes are present in two identical copies, although polyploid cells have multiple copies of chromosomes and haploid cells have single copies. The chromosomes are arranged and displayed (often ...karyotype.
