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1、Alterationsinsexchromosomenumber（教材上册p142）TurnerSyndrome(45,X)1in2500livebornfemalesCharacteristicsShortstature&WebbedneckOvariandysgenesis,primaryamenorrhea,infertilityAbsenceofsecondarysexcharacteristicsUnderdevelopedbreasts;widenipples性腺发育不全综合症身材矮，蹼颈，肘外翻，原发性闭经，生殖器幼稚，索状性腺（结缔组
2、织，无卵泡）。成因：早期卵裂过程中染色体不分离。多数有生育能力，少数卵巢功能异常，2/3伴有轻度智力低下，并有患精神病的倾向。TwoofthethreeXchromosomesareinactivated.1in800malesTallwithdisproportionatelylongarms/legsKlinefeltersyndrome(47,XXY)（克氏综合症）1in100mentallyretardedmales1in10infertilemalesPoorlydevelopedsecondarysexcharacteristicsTes
3、ticulardysgenesisAlterationsinsexchromosomenumber先天性睾丸发育不全综合征女性体态，有女性化乳房，胡须少，皮肤较嫩；睾丸小而硬，无精子，但睾丸间质细胞不萎缩；智力低下。1in750~1500malesTallstatureXYYsyndrome(47,XYY)1in30maleprisonpopulationsPredispositiontoviolent,criminalbehavior＞180cm:1/200＞190cm:1/30＞200cm:1/10Alterationsinsexchromoso
4、menumberAlterationsinautosomenumber（教材下册P41）DownSyndrome(trisomy21syndrome)病因：比正常人多了一条21号常染色体唐氏综合症：智力低下，身体发育缓慢。常表现为特殊的面容,较敏感和快乐,寿命短。CharacteristicsGrowthretardationVaryingdegreesofmentalretardationFlattenedfaceUpwardslantingoftheeyeswithepicanthalfolds1in600~800newbornsDownSynd
5、rome(trisomy21syndrome)皮肤折痕DownSyndromeandMaternalAgeAsmaternalageincreases,theriskofhavingababywithDownsyndromeincreasesAtage20lessthan1in1000birthsresultsindownsyndromeAfterage40,greaterthan1in100birthsresultsinDownsyndrome如果经适当教育，唐氏症患者依然可以有很好的表現Trisomy18:Edward’sSyndrome(47,
6、+18)smallatbirth,veryslowgrowing,mentalretardation,malformedfeet,heartmalformations.Forunknownreasons,80%ofliveborntrisomy18babiesarefemale.EdwardsSyndrome(trisomy18syndrome)Trisomy13:PatauSyndrome(47,+13)Facialmalformations,eyedefects,extrafingersortoes,feetwithprotrudingheels
7、,malformationsofthebrain,nervoussystem,heartdefectsFrequenciesofTrisomiesinSpontaneousAbortionsSomeChromosomesarerarelyseenastrisomiesinabortuses(1,5,11,17,19)Otherchromosomesoccurfrequentlyastrisomies(16)Thereasonsforthesedifferencesarenotclear.Aneuploidy:AlterationsinChromoso
8、meNumberAlterationsinchromosomenumbercancausepolyploid
