Thursday, 6 March 2008

non syndromic inheritable teeth abnormalities

ความผิดปกติของฟันแบบพันธุกรรมไม่เข้ากลุ่มอาการ non syndromic inheritable teeth abnormalities

1. Dentinogenesis imperfecta (DI)

ถ่ายทอดแบบ AD

ชุดฟันที่เป็นปัญหา ทั้งฟันน้ำนมและฟันแท้

ลักษณะฟัน เทา เหลือง น้ำตาล ตัวฟันกว้าง คอแคบ เหมือนดอกทิวลิป อีนาเมล เปราะ แตกง่าย เหลือแต่เนื้อฟัน (Dentin)

ลักษณะรังสี ฟันเป็นของแข็งทึบ ไม่มีโพรง ไม่มีช่องรากฟัน

ลักษณะอื่นที่พบ บางรายมีหูหนวก (DFNA39 mutation ร่วมด้วย)

ตำแหน่งยีน โครโมโซม คู่ที่ 4 4q21.3 ยีน code dentin sialophosphoprotein (DSPP) ซึ่งเป็นโปรตีนที่เป็นองค์ประกอบสำคัญมากกว่า 50 % ในเนื้อฟัน ในส่วนที่ไม่ใช่คอลลาเจน A15V, P17T, V18F, Q45X

Differential diagnosis กับ osteogenesis imperfecta แต่โรคนี้มีแต่ผิดปกติที่ฟัน

การจำแนกชนิด
1. DI type I with OI (Osteogenesis imperfecta)
2. DI type II without OI
3. DI type III พบน้อยมาก และลักษณะกลับกันคือ เนื้อฟันมากไปเหมือนเปลือกหอย แต่ก็พบการกลายพันธุ์บนยีนที่ตำแหน่งเดียวกันกับ type II (allelic variant)







2. Dentin Dysplasia type I and II (DD I and DD II)

Type I ชื่ออื่น Rootless teeth, Radicular Dentin Dysplasia

ถ่ายทอดแบบ AD, มีรายงาน AR homozygous mutation ของยีน NFIC

ตำแหน่งยีน ยังไม่ทราบ

ลักษณะฟัน ภายนอก จะมีสีและรูปร่างค่อนข้างปกติ อาจจะสีเงาๆ ออกฟ้า หรือ น้ำตาลเล็กน้อยได้บ้าง
อาจเป็นฝีได้

ลักษณะ systemic มีรายงานพบลักษณะฟันแบบนี้ในคนไข้ที่มีลักษณะของ EDS type III (hypermobility syndrome ได้) มีรายงาน sclerotic ของ long bone ได้

ลักษณะทางรังสี ไม่มีรากฟันเลยและ มีรอยดำรอบๆ apical area หรือมีรากสั้นๆ ไปจนกระทั่งมีรากยาวปกติ แต่โพรงฟันแคบมาก และอาจมีหินปูนในโพรงฟัน (pulp)
















Type II OMIM #125420 (Gene DSPP 125485)
ชื่ออื่น
DTDP2DENTIN DYSPLASIA, SHIELDS TYPE IICORONAL DENTIN DYSPLASIAANOMALOUS DYSPLASIA OF DENTINPULPAL DYSPLASIAPULP STONES

ถ่ายทอดแบบ AD น่าจะเป็น allelic variant ของ DI-II พบในตระกูลเดียวกันได้

ตำแหน่งยีน 4q21.3 DSPP gene Y6D (Rajpar et. al 2002)

ลักษณะฟัน ฟันน้ำนมจะมีสีเหลือง โปร่งแสง และไม่มีโพรงฟันเลย ส่วนฟันแท้จะมีสีภายนอกปกติ รากปกติ แต่โพรงฟันขึ้นไปถึง ตัวฟันด้านบน บานออกคล้ายเปลวไฟ หรือ thistle tube

Sunday, 2 March 2008

Gene patenting: Pros and Cons

Pros

Centralization, specialization

Rewarding, Incentives for further inventions

No further secrets

Cons

Quality control

Accessibility

Cost

Lost of expertise

Right of previous contributed researchers

I have found this below interesting essay about gene patenting wrote by an anonymous author in the internet.

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I. Patents for Biotechnology
(Pros and cons of genetic patents)
Biotechnology is closely related to drug industries. 90% of biotechnology sales in the
U.S. are from pharmaceuticals. The number of granted biopharmaceutical patents in the
U.S. is 5170 in 2001, while only 533 in Europe.1 This result depends on the difference
between them about genetic patents policy.
There are significant advantages for allowing genetic patents. First, the patents in this field
clearly promote invention. The drug industry is the field where patent protection is easier to
enforce because of the relative simplicity of the industry and its products. Second, the
patents encourage many entities get into the research. Until the 1970s, nearly all molecular
biology research was government or university sponsored. After genetic patents were
admitted in the U.S., small firms can raise funds for research activities by making their
knowledge into assets through patent system. New drugs require knowledge from broad
fields, so the collaboration among many entities is effective for making good research.
Third, the patents have an effect to promote diffusion of new research by filing research
1 Derwent Intellectual Property. Patenting in the biopharmaceutical industry- comparing
the US with Europe. December 2002.
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contents.
On the other hand, disadvantages of allowing genetic patents are as follows. First, too
many patents may adversely slow down research activities. As the risks to infringe existing
patents grow, pharmaceutical industries are forced to specialize in particular fields.
Increased costs for litigation concerning patents might also impede research activities.
Second are the adverse effects on the diffusion of the products. Allowing genetic patents
will lead the price of drugs increase due to the license fees. This price increase can diminish
high social rates of return of the drugs by restraining their spreading to the public.
Furthermore, patent holders might ask the withdrawal of drugs that infringe their patent
rights, even if the drugs are already widely used.
(Recommendation)
I recommend that EU should make genetic patents easier as the U.S. already did by
following reasons. First, the needs for genetic patents from creators are very high. The
number of biopharmaceutical patent applications has been increasing continuously. It has
become from 430 in 1992 to 3544 in 2001.2 It means that creators regard genetic patents as
2 In the U.S., the number of application in this field is 34,527 in 2001. Ibid.
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useful to advance their innovative activities.
Second, relaxation of the conditions of genetic patents is essential to promote the
international competitiveness of Europe in biotechnology. Industries in this field have
broadened their activities worldwide (We must note that leading companies in the U.S. and
Japan has already applied and held biopharmaceutical patents in Europe.). Collaboration
among many entities including government, universities and industries is important in
biotechnology to accumulate knowledge from various fields. Genetic patents will promote
the growth of firms and universities addressing the challenging research in Europe.
How do we deal with the disadvantages expected? The problem of patent thickets might
occur, but it can be solved by the vertical integration and cross licensing among patent
holders. As for the litigation, some special measures to restrict the increase of the costs (e.g.
compulsory arbitration) are the possible solution.
The problem of diffusion is more serious. I think this problem should be solved by the
support from the government. It takes enormous costs to make innovations or inventions in
biotechnology. The costs should be shared properly between creators, consumers and the
government. The subsidies from the government will contribute to restrain the price
increase due to the license fees. Furthermore, compulsory licensing system will prevent
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creators from keeping their patented knowledge unused.
By introducing these methods, European biotechnology firms can increase their
incentives for innovative activities, which will strengthen their competitiveness in the
world. The welfare of European citizens will be also promoted by the development of new
drugs and treatments using innovative biotechnology. We must note that effective measures
to secure the appropriate diffusion, namely, the speedy distribution of the products with
reasonable price, should be implemented at the same time by governmental assistance.
Overall, this is a strong answer. The author clearly states both the pros and cons of
patent protection for biotechnology. Note how each point is clearly emphasized (e.g.
“first”, “second”, “third”) making it easy for the reader to follow the argument.
Similarly, in making policy recommendations, the author again clearly states the reasons
why the recommendation is made. Also, the author does a good job of noting the
potential problem of diffusion, and creatively offers a potential solution.
One caveat: the answer could be strengthened with a stronger introduction. Although
each section is well-written, it would help to have a statement of the final
recommendation at the beginning of the answer, so the reader can evaluate the pros and
cons of patenting with the final recommendation in mind.