【問題】Tay-Sachs Disease's Three Levels of Classification

[OoLucyoO 10]

雖然今天已經考完這部份

可是我還是不太懂

Tay-Sachs Disease, 也就是所謂的"唐氏症"

我昨天晚上複習的時候讀到

According to Ch.14 in Campbell's Biology p.261 :

At the organismal level' date=' the Tay-Sachs allele qualifies as recessive.

At the biochemical level, it is incomplete dominant.

At the molecular level, the normal allele and theTay-Sachs allele are codominant.

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How come?

I am really confused... ~_~

[--◎笨笨糖◎-- 10]

恩...其實我英文不好...

上網查一下資料其實很多喔...

之前教遺傳的時候有講

第二十一對染色體三體變異

就是原本該是兩條的東西變成三條了...

你可以用wikipedia查查看=ˇ=

其實它資料還不錯多

我剛看了一下中文的

算是詳細.

英文應該更多

[starjimmy 10]

唐氏症=Down's Syndrome, which is usually caused by trisomy 21.

TS-Disease is a disease with fatty acid metabolism problem. i.e., your lysosome do not have an enzyme to degrade certain lipid, which can accumulate and end up detrimental to your nervous sys.

[OoLucyoO 10]

唐氏症=Down's Syndrome, which is usually caused by trisomy 21.

TS-Disease is a disease with fatty acid metabolism problem. i.e., your lysosome do not have an enzyme to degrade certain lipid, which can accumulate and end up detrimental to your nervous sys.

mmm

ic

but why is it classified in three different levels?

recessive, codominant, and incomplete dominant...

[OoLucyoO 10]

恩...其實我英文不好...

上網查一下資料其實很多喔...

之前教遺傳的時候有講

第二十一對染色體三體變異

就是原本該是兩條的東西變成三條了...

你可以用wikipedia查查看=ˇ=

其實它資料還不錯多

我剛看了一下中文的

算是詳細.

英文應該更多

很顯然是我自己翻錯(靠發音翻的)

因為我知道唐氏症是第二十三對染色體出問題

但似乎跟父母年紀比較相關

只有4%可能遺傳

這以前國中生物也有教

更詳盡的資料網路上都有

只是一直都找不到為什麼要分三個層次

我學校老師超厭惡wikipedia

我不解為什麼大家這麼愛用欸

任何人都可以在上面亂打些什麼

[--◎笨笨糖◎-- 10]

我會對照之前學過的資料啦..

就某種狀態而言他還是有其參考價值

再不然就到醫學的專業網站搜尋囉

不是23對是21對噢

然後唐氏症是性聯遺傳啊...

生女孩就會遺傳到

三個層次?

...就是遺傳的顯性，不完全顯性，和隱性吧?

這方面的資料有點少

我覺得你先把性聯遺傳唸一下會比較懂...

我記得的是這樣

搞不好記錯

參考就好

[OoLucyoO 10]

噢對(typo...sorry)

性聯遺傳...一般sex-linked都是男生吧

不過Tay-Sachs Disease 不是唐氏症

嗯嗯

我再問問看為什麼要這麼分好了~_~

[starjimmy 10]

recessive in that you have to have both mutant allele for you to phenotypically diseased.

when you look at the biochemical level of the process of degrading the lipid, indeed heterozygotes are less efficient in degrading the lipid, therefore showing the incomplete dominance. In the molecular level, since both mutant and normal alleles get expressed, it is consider codominance.

[OoLucyoO 10]

Oh!!!

ic

Thank you very much!!!