染色体出了问题   Chromosomal Problems

现代科学研究发现了大量非典型的染色体组合类型。下面描述的仅仅是这中间最要害的组合类型。通常，非典型染色体组合涉及XX或XY的非常规结合。人口中有0.5%-1.0%的发生率。
Modern research has found a number of possible atypical chromosomal conditions. The following desribes only the most important of them. As a rule, they concern deviations from the regular XX- or XY-combination. They are found in ca. 0,5 to 1 percent of the population.
 

女孩

1.  唐纳氏综合征（Turner Syndrome），既仅有单一X染色体存在，第二条不见了（X0）。表现的症状就是以生长矮小为特征，卵巢发育不良，缺乏月经，也不能生育。激素治疗能最低程度地稍微改善体格外貌。该综合征的发生率为每3000个活产中有一个。

2. 三联综合征（Triple X Syndrome） (XXX), 既除了两条常规的XX染色体之外，存在着第三条X染色体。患有该综合征的女孩，和随后长成的女人，在外表上会和其她女性不同。她可能生育力底下，也可能有精神症状。该综合征在每1000个活产中有一个发生率。

 In Girls

1. The so-called Turner Syndrome, i.e. only a single X-chromosome is present, the second one is missing (X0). The condition is characterized by stunted growth, a deficient development of ovaries, absent menstruation and absent breast development as well as infertility. Hormonal treatment can at least somewhat normalize the physical appearance. The syndrome is found in one of ca. 3000 live births.

2. The Triple X Syndrome (XXX), i.e. a third X-chromosome is present in addition to the two regular ones. The girl, and later the woman, will not differ from others in her appearance. However, she is likely to be less fertile, and she may also have psychological problems. The syndrome is found in one of ca. 1000 live births.
 

In Boys

1. （Klinefelter Syndrome）, 既，染色体组合为XXY（或非常罕见的XXXY）。患者表现为睾丸发育不良，雄性激素水平低，乳房发育，有不成比例的上下肢，不能生育和可能有渐进发展的智力缺陷。在青春期给予激素治疗常常能够发育出男性的身体特征。该综合征在1000个活产中会有一例。

2. （XYY Syndrome）， 表现为性器官畸形和生育力低下，也可能有渐进发展的智力缺陷。该综合征在1000个活产中会有一例。

 In Boys

1. The so-called Klinefelter Syndrome, i.e. the chromosomal combination XXY (or, very rarely, XXXY). It manifests itself in underdeveloped testicles, a low level of testosterone, a growth of breasts, disproportionate arms and legs, infertility and an increased likelihood of mental deficiency. Hormonal treatments in adolescence can often achieve a masculinization of the body. The syndrome is found in one of ca. 1000 live births.

2. The XYY Syndrome manifests itself in malformations of the sex organs and reduced fertility. There is also an increased likelihood of mental deficiency. The syndrome is found once in ca. 1000 live births.