r****r
发帖数: 9 | 1 Assume there are n genes on a chromosome (say chromosome 1), each person has a
pair of such chromosome. Each child will randomly inherit one chromosome of t
he pair. Given the person has m children, what's the probability of all 2n gen
es have been inherited?
Assume in miosis
(1) there are 0 recombination between the chromosome pair
(2) there are infinite large recombinations between the chromosome pair
under assumption (1), the probability is 1-(1/2)^(m-1)
under assumption (2), the probability |
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h*i
发帖数: 3446 | 2 当然是汉藏近。汉日都比汉人与东南亚人近。
O3-M134几乎只出现在说汉藏语系的，或者被汉藏语系人殖民的，或者与汉藏语系人有
接触的区域当中：
From wikipedia:
The subgroup O3a5-M134 is particularly closely associated with Sino-Tibetan
populations, and it is generally not found outside of areas where a Sino-
Tibetan language is currently spoken or that are historically supposed to
have undergone Chinese colonization or immigration, such as Korea, Japan,
Vietnam, Malaysia, the Philippines, and Indonesia. However, its presence
among non-Sino-Tibetan populations is alw... 阅读全帖 |
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r**********n
发帖数: 3914 | 3 Making Magnolia crappie
The Magnolia crappie is a cross between a male blackstripe crappie and a
female white crappie. The blackstripe crappie is a color variant of the
black crappie that occurs naturally in low numbers in some Mississippi
impoundments. The blackstripe crappie — also called a blacknose crappie —
is recognized by a narrow, dark stripe from the dorsal fin forward down the
top of the head and continues on the underside of the head to the back of
the mouth.
The hybrid offspring of t... 阅读全帖 |
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H********g
发帖数: 43926 | 4 Genes known to be contained on the Y chromosome[edit]
As of the year 2000, a number of genes were known to be Y-linked, including:
[3]
ASMTY (acetylserotonin methyltransferase),
TSPY (testis-specific protein),
IL3RAY (interleukin-3 receptor),
SRY (sex-determining region),
TDF (testis determining factor),
ZFY (zinc finger protein),
PRKY (protein kinase, Y-linked),
AMGL (amelogenin),
CSF2RY (granulocyte-macrophage, colony-stimulating factor receptor, alpha
subunit on the Y chromosome),
ANT3Y (aden... 阅读全帖 |
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r*****e
发帖数: 176 | 5 赞一个，这个才是科学的态度。 楼主估计是一个皮一拽就多老长的老WSN，幸运的有了
点钱，就发贴想骗年轻姑娘做老婆。。。
Brainy sons owe intelligence to their mothers
GLENDA COOPER
Intelligent men owe their brains to their mothers, according to research
published today in The Lancet.
Growing evidence shows that several genes which determine intelligence
appear to be located on the X chromosome, the one men inherit from their
mothers .Any mutation on the X chromosome has more effect on a man than a
woman because a woman inherits X chromosomes from both her... 阅读全帖 |
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l*********e
发帖数: 5483 | 6 More reasonable!
Brainy sons owe intelligence to their mothers
GLENDA COOPER
Intelligent men owe their brains to their mothers, according to research
published today in The Lancet.
Growing evidence shows that several genes which determine intelligence
appear to be located on the X chromosome, the one men inherit from their
mothers .Any mutation on the X chromosome has more effect on a man than a
woman because a woman inherits X chromosomes from both her parents, which
tends to dilute the gene's... 阅读全帖 |
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h*i
发帖数: 3446 | 7 From wikipedia:
"Y-chromosome haplogroup O3 is a common DNA marker in Han Chinese, as it
appeared in China in prehistoric times. It is found in more than 50% of
Chinese males, and ranging up to over 80% in certain regional subgroups of
the Han ethnicity.[28] However, the mitochondrial DNA of Han Chinese
increases in diversity as one looks from northern to southern China, which
suggests that some male migrants from northern China married with women from
local peoples after arriving in Guangdong, ... 阅读全帖 |
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m*********a
发帖数: 3299 | 8 Y-chromosome haplogroup O3 is a common DNA marker in Han Chinese, as it
appeared in China in prehistoric times. It is found in more than 50% of
Chinese males, and ranging up to over 80% in certain regional subgroups of
the Han ethnicity.[67] However, the mitochondrial DNA of Han Chinese
increases in diversity as one looks from northern to southern China, which
suggests that some male migrants from northern China married with women from
local peoples after arriving in Guangdong, Fujian, and other... 阅读全帖 |
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s*******e
发帖数: 1389 | 9 Only the tips of the Y and X chromosomes recombine. The tips of the Y
chromosome that could recombine with the X chromosome are referred to as the
pseudoautosomal region. The rest of the Y chromosome is passed on to the
next generation intact.
http://en.wikipedia.org/wiki/Y_chromosome#Recombination_inhibit |
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w********9
发帖数: 8613 | 10 看印度的婆罗门族群
http://www.nature.com/jhg/journal/v54/n1/full/jhg20082a.html
Many major rival models of the origin of the Hindu caste system co-exist
despite extensive studies, each with associated genetic evidences. One of
the major factors that has still kept the origin of the Indian caste system
obscure is the unresolved question of the origin of Y-haplogroup R1a1*, at
times associated with a male-mediated major genetic influx from Central Asia
or Eurasia, which has contributed to the higher castes... 阅读全帖 |
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t**x
发帖数: 20965 | 11 wiki 上的：
Physical traits
47,XYY boys have an increased growth velocity from early childhood, with an
average final height approximately 7 cm (3") above expected final height.[4]
In Edinburgh, Scotland, eight 47,XYY boys born from 1967–1972 and
identified in a newborn screening program had an average height of 188.1 cm
(6'2") at age 18—their father's average height was 174.1 cm (5'8½"),
their mother's average height was 162.8 cm (5'4").[1][5] The increased gene
dosage of three X/Y chromosome... 阅读全帖 |
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s********e
发帖数: 1596 | 12 The major risk for advanced maternal age is chromosomal abnormalities, i.e.
trisomy (3 copies of a particular chromosome) or monosomy (a single copy of
chromosome) caused by errors of meiosis of the oocytes. Most monosomy cases
die early during embryogenesis or early fetal stage. For trisomies, the ones
that can survive are trisomy 13, trisomy 18 and trisomy 21, with the last
one being Down Syndrome. In most cases, trisomy 18 and 13 die before they
reach 1 year of age. Trisomy 21 can live to adu... 阅读全帖 |
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k**n
发帖数: 6198 | 13 哇，第一段就很扎眼球，我的拙劣翻译如下
男性的Y染色体， 垃圾很多，有用特质很少，拒绝社会化，趋于退化.
我遁了............
"Until recently, the Y chromosome seemed to fulfil the role of juvenile
delinquent among human chromosomes — rich in junk, poor in useful
attributes, reluctant to socialize with its neighbours and with an
inescapable tendency to degenerate. The availability of the near-complete
chromosome sequence, plus many new polymorphisms, a highly resolved
phylogeny and insights into its mutation processes, now provide new avenues
for inve... 阅读全帖 |
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b*s
发帖数: 82482 | 14 In 2003 a groundbreaking historical genetics paper reported results which
indicated that a substantial proportion of men in the world are direct line
descendants of Genghis Khan. By direct line, I mean that they carry Y
chromosomes which seem to have come down from an individual who lived
approximately 1,000 years ago. As Y chromosomes are only passed from father
to son, that would mean that the Y is a record of one’s patrilineage.
Genghis Khan died ~750 years ago, so assuming 25 years per gener... 阅读全帖 |
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s***e
发帖数: 911 | 15 你举的例子都太复杂了. 我举个更简单的, 已经足以说明很多生物复杂问题需要依赖直
接测量才能有效定量化. Mitotic chromosome究竟是有个rigid protein scaffold,
DNA绕在上面; 还是一个DNA network, protein只是提供网格节点的稳定性? 以前猜东
猜西, 也不如抓住一个chromosome, 测量它的力学响应, 以及MNase对这个力学响应的
理解深刻. 结论是mitotic chromosome是一个DNA network. 而且是一个非常松散的网
络.
Poirier MG, Marko JF. Free in PMC Mitotic chromosomes are chromatin networks
without a mechanically contiguous protein scaffold. Proc Natl Acad Sci U S
A. 2002 Nov 26;99(24):15393-7. Epub 2002 Nov 18. |
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g*********d
发帖数: 233 | 16 The role of small non-coding RNAs in genome stability and chromatin
organization
http://jcs.biologists.org/content/123/11/1825.full
Josien C. van Wolfswinkel and René F. Ketting*
Journal of Cell Science 123, 1825-1839
© 2010. Published by The Company of Biologists Ltd
doi:10.1242/jcs.061713
Summary
Small non-coding RNAs make up much of the RNA content of a cell and have
the potential to regulate gene expression on many different levels.
Initial discoveries in the 1990s and early 21st centur... 阅读全帖 |
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c*****g
发帖数: 66 | 17
对你而言，如果你只生一个，确实是。对你儿子而言，他从你老婆那里还拿了一半，所
以他不缺什么。对人类而言，只要群体足够大，不丢失。
你可以认为全人类就那么几条。这个几可能是很大的数字，但是基本上可以归结为几个
大的group，group内部区别不大。
同(
有基因突变的，y-chromosome的haplogroup基本上就是突变产生的。因为人类的交配有
地理上的分离，所以往往某些haplogroup只在某些地方出现，你和你的后代都在一个地
方生活，你的Y就一直留在那里了。
这个adam的两个儿子是概念上的两个儿子，应该理解为经过了很长时间后，那个y-
chromosomal adam产生的两个和adam不一样的后代，不是adam生了俩儿子和他不一样。
如果那样, 那肯定是别的原因，这个你懂的。
y chromosome可能会和x chromosome重组，这个比较少见。但是应该不会和自己重组（
因为只有一条），这个应该是很罕见的。
你可以把线粒体dna理解成和y是一样的遗传方式，线粒体隔代可不减半，这里不存在减
数分裂。 |
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y**********n
发帖数: 478 | 18 经典遗传学的东西怎么跟现代基因学联系起来有时候确实很头大。我试着解释下，先贴
一段wiki上的：
“An allele (UK play /ˈæliːl/ or US /əˈliːl/)
is one of two or more forms of a gene or a genetic locus (generally a group
of genes).[1][2] The form "allel" is also used, an abbreviation of
allelomorph. Sometimes, different alleles can result in different observable
phenotypic traits, such as different pigmentation. However, many variations
at the genetic level result in little or no observable variation.
Most multicell... 阅读全帖 |
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l*******i
发帖数: 153 | 19 首先有一个概念要明确：目前说的ES细胞，都是in vitro culture的，与in vivo的不
一样。
ES细胞分为naive和prime两个stage
1)naive stage：ES colony在形态上看起来更“致密”，呈三维结构，对胰酶不敏感（
即胰酶消化不会诱导其凋亡）。对小鼠ES而言，naive的ES来源于inner cell mass(ICM
)。此stage的ES self-renewal更迅速，population double大概只需要12-14小时。对
于其self-renewal的维持需要LIF，stat3,BMP4等。雌性小鼠naive ES的另一个显著特
点是X chromosome reactivation,而在其他类型的细胞中有一条X chromosome是失活的
。从全能性角度来讲，naive ES是真正具有全能性的，能形成完整的个体。
2）prime stage：对小鼠而言，其来源于postimplantation epiblast,是naive stage
的下一个阶段，其形态看起来与naive ES明显不一样，呈“二维”结构，即colony... 阅读全帖 |
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f*****h
发帖数: 228 | 20 给你贴了吧，大家想用都可以
#!/usr/bin/perl -w
#############################################
#Author: Jiang Li
#email: r**********[email protected]
#Creat Time: Tue 23 Oct 2012 01:37:54 PM CDT
#Vanderbilt Center for Quantitative Sciences
#############################################
use strict;
use warnings;
=pod
=head1 SYNOPSIS
Given a genbank format file (.gb), parse its feature parts (mRNA feature to
get exon regions) to get information like transcript id, gene name, etc.,
and store the result in gtf format
=he... 阅读全帖 |
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v*******e
发帖数: 11604 | 21 楼主要的例子来了：60楼wwwhu给的link里面有一个例子，一个中国人只有22对染色体
，他的妻子老是流产；他自己是家族近亲繁殖的结果；如果他留在家族里面近亲繁殖就
有可能产生22对染色体的新人类：（下面的link里面有从23对到22对的路线图，和我前
面说的一样，必须有家族里面的近亲繁殖；下面说的纯属科学探讨，无关伦理，也非对
他不敬：如果他父母再生个女的44条的，他们两个就可以繁殖出个新人类；或者他和他
母亲也可以；或者用他的精子来给女性大面积播种，也会有新的45条染色体后代存活，
把这些人选出来可以繁殖出一些44条的，这些人就可以繁殖出一个新人类）
Barry:
Great article. A Chinese doctor contacted me a few years ago about a man
with 44 chromosomes who was perfectly normal but suffering from multiple
miscarriages (well, his wife was suffering from the miscarriages)... 阅读全帖 |
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A*******s
发帖数: 9638 | 22 Agree with acne.
Adrenoleukodystrophy (ALD) is one of a group of genetic disorders called the
leukodystrophies that cause damage to the myelin sheath, an insulating
membrane that surrounds nerve cells in the brain. People with ALD accumulate
high levels of saturated, very long chain fatty acids (VLCFA) in the brain
and adrenal cortex because they do not produce the enzyme that breaks down
these fatty acids in the normal manner. The loss of myelin and the
progressive dysfunction of the adrenal gl... 阅读全帖 |
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A*******s
发帖数: 9638 | 23 Agree with acne.
Adrenoleukodystrophy (ALD) is one of a group of genetic disorders called the
leukodystrophies that cause damage to the myelin sheath, an insulating
membrane that surrounds nerve cells in the brain. People with ALD accumulate
high levels of saturated, very long chain fatty acids (VLCFA) in the brain
and adrenal cortex because they do not produce the enzyme that breaks down
these fatty acids in the normal manner. The loss of myelin and the
progressive dysfunction of the adrenal gl... 阅读全帖 |
|
D*****i
发帖数: 8922 | 24 十多年前，研究DNA的人发现从蒙古到中亚的上千万人共享一个大约一千年前的祖宗。
他们猜测这是由铁木真领导的蒙古人的征服造成的。最近又有研究者研究了游牧民族后
代的DNA数据，发现这个超级祖宗生活在2500年前，也就是说这个游牧民族超级祖宗不
是铁木真或者其较近的亲属。
The Y-chromosome haplogroup C3*-Star Cluster (revised to C2*-ST in this
study) was proposed to be the Y-profile of Genghis Khan. Here, we re-
examined the origin of C2*-ST and its associations with Genghis Khan and
Mongol populations. We analyzed 34 Y-chromosome sequences of haplogroup C2*-
ST and its most closely related lineage. We redefined this paternal linea... 阅读全帖 |
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W*****B
发帖数: 4796 | 25 全世界只有20几个人
An 11-Year-Old Got Most Of Her Genes From Her Dad, And Almost None From Her
Mom
BuzzFeed News Reporter
An 11-year-old girl from the Czech Republic was born with genes that came
almost entirely from her father, instead of half from each parent.
Only about 25 people in the world — all girls — have been reported with
this genetic syndrome, and the Czech girl appears to be the first to have
inherited it without developing cancer.
“Ten to fifteen years ago, we didn’t think this condition w... 阅读全帖 |
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b********n
发帖数: 38600 | 26 “As you are speaking as the oracle of science, tell us, what exactly is a Y
chromosome?” Cruz responded on Twitter. “And at what age of gestation
does science tell us that an unborn child feels physical pain?”
He may have picked the wrong opponent – Ocasio-Cortez, it transpires, holds
an award for microbiology from MIT.
Despite reports in the past of the two lawmakers, surprisingly, finding
common ground on other issues, Ocasio-Cortez did not let the slight go
unaddressed. Touting her scientific... 阅读全帖 |
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c**i
发帖数: 6973 | 27 Your posting is meaningless.
(A) Background.
(1) Linda Hopkins, Common "Abnormal" Ultrasound Findings: What Should I
tTell My patients? UCSF, June 5, 2008. http://www.ucsfcme.com/2008/slides/mob08003
/HopkinsCommonAbnormalUltrasoundFindings.pdf
The first two discussed ultrasound findings are echogenic intracardiac
focus (EIF) and choroid plexus cyst (CPC).
(a) EIF
(i) What is it?
An echogenic (bright) spot in the left cardiac ventricle
Correlates to mineralization (calcification) of the pap... 阅读全帖 |
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c**i
发帖数: 6973 | 28 (1) Short of waiting until birth, cytogenetics or chromosome banding is quite
definitive.
Amniocentesis is required to obtain cells from the fetus. There is risk for
the procedure.
Also, a study with fetal cells may fail, just like any other study/
experiment. In early 1990s, I asked and obtained permission from the
cytogenetics chief at Massachusetts General Hostial to observe. He was doing
the fluorescent in situ hybridization (FISH) to see if the fetus was male
or female; the parents carried... 阅读全帖 |
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j*******y
发帖数: 89 | 29 SAN DIEGO, Oct. 17, 2011 /PRNewswire/ -- Sequenom, Inc. (NASDAQ: SQNM), a
life sciences company providing innovative genetic analysis solutions, today
announced that its wholly-owned subsidiary, Sequenom Center for Molecular
Medicine (Sequenom CMM), launched its noninvasive proprietary MaterniT21
laboratory developed test (LDT). The MaterniT21 LDT detects a genetic
chromosomal anomaly known as Trisomy 21, the most common cause of Down
syndrome. The test is now available to physicians upon requ... 阅读全帖 |
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h********y
发帖数: 3778 | 30 羊水穿刺是从羊水里面分离胎儿的细胞
fetal cells are separated from the extracted sample. The cells are grown in
a culture medium, then fixed and stained. Under a microscope the chromosomes
are examined for abnormalities.
Maternit21: The test operates by sampling cell-free DNA in the mother's
blood, which contains some DNA from the fetus. The proportions of DNA from
sequences from chromosome 21, 18, or 13 can indicate whether the fetus has
trisomy in that chromosome
为什么前者是diagnostic的，后者不是。从技术的nature上来说，这两者有什么不同。 |
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l**********n
发帖数: 8443 | 31 caused by inactivation of the INI1 gene (SMARCB1)on chromosome 22q which
functions as a classic tumour suppressor gene.
Inactivation of INI1 can occur via deletion, mutation, or acquired UPD.
Uniparental disomy (UPD) occurs when a person receives two copies of a
chromosome, or part of a chromosome, from one parent and no copies from the
other parent.
In a recent study[4], SNP array karyotyping identified deletions or LOH of
22q in 49/51 rhabdoid tumours. Of these, 14 were copy neutral LOH (or
ac... 阅读全帖 |
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G****a
发帖数: 10208 | 32 A child has been born in the US after physicians and scientists used next-
generation sequencing to select an embryo for in vitro fertilization.
This birth marks the first time that sequencing has been used to screen
embryos for IVF, a process that generally sees only around 30 percent of the
embryos that are selected actually successfully implant, likely due to
chromosomal or genetic defects.
Although other genetic tests screening methods have already been introduced
to identify candidate embry... 阅读全帖 |
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d***8
发帖数: 2039 | 33 The skin color (pigment) is determined by the genes at X chromosomes. TW's
son inherited the X chromosome from Mom (White), so the son looks completely
white.
TW's daughter has two chromosomes, one from Mom and one from TW. |
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l******n
发帖数: 11737 | 34 “Genetically speaking, anyways. I've been playing ME2 again, and she just
spoke about her genetic enhancements and whatnot. She mentions that her
genome is based on her father's, and he didn't even bother to get a second X
chromosome, not even double his own. He just modified the Y chromosome. He
probably just disabled the SRY gene on the Y chromosome, which would make
Miranda anatomically female, but infertile... and that explains why Miranda
is unable to have children.” |
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f*******g
发帖数: 245 | 35 how come ? I am confused by this statement. Have a calculation:
Grand parentals: X1Y vs X2X3
Father: X2(or3)Y vs Mother: X4X5
Daughter: X2(or3)X4(or5)
now, the genetical material (x chromosome) between father and his brother
has 50% identical.
The genetical material (x chromosome) between father and dauthter has 50%
identical.
Conclusion: the chance for a female to share identical X chromosome with her
uncle is 25%. |
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f*******g
发帖数: 245 | 36 it is the chance to share a x chromosome not genetical material. En, the
chance for a daughter to share a identical x chromosome with her father is
100%.
so the correct answer is 50% chance for a female to share identical X
chromosome with her 叔叔. this should be right
her |
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D*****r
发帖数: 6791 | 37 http://www.bbc.co.uk/news/10132762
'Artificial life' breakthrough announced by scientists
By Victoria Gill Science reporter, BBC News 20 May 2010
Scientists in the US have succeeded in developing the first living cell to
be controlled entirely by synthetic DNA.
The researchers constructed a bacterium's "genetic software" and
transplanted it into a host cell.
The resulting microbe then looked and behaved like the species "dictated" by
the synthetic DNA.
The advance, published in Science, ... 阅读全帖 |
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P******l
发帖数: 1648 | 38 探讨话题:
3 现今全人类的2号染色体长臂的2q13–2q14.1位置上，都有一段“789个碱基字符的序
列”，它是男人和女人都有的标记。 所有人基本(注意我把我的理解从完全改为基本)
相同 (我们可以称它为“人类DNA的第一个标记”), 这可以作为一个现存人类同源
的证据
for both chromatids
==============
思路过程:
http://www.bydnacoding.org/CHT2-P1.html (这一段是copy paste)
亲子鉴定方法：
常染色体亲子鉴定:
由于常染色体一半来自父亲、一半来自母亲，在常染色体亲子鉴定中，可以确定孩子的
亲生父母。
孩子的每对(两条)常染色体一条来自父亲、一条来自母亲，因此，可以通过比较父、母
和子女在常染色体特定位点上DNA字符代码的序列，来判定亲子关系。
例如，孩子在染色体某个位点上的一串DNA字符代码是“TCAT TCAT TCAT TCAT TCAT
TCAT TCAT TCAT”，这8个“TCAT”的重复，可以看成是一个“遗传标记”。他的母亲
或父亲的DNA，在此位点上一定有这样的8个“TCA... 阅读全帖 |
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P******l
发帖数: 1648 | 39 从基因看人类的起源
文/张纪德
本文原发表于《中信》月刊总637期，由“中国信徒布道会”出版，蒙允许转载，特此
致谢。
在二十世纪，一般科学家都认为猿猴类与人类的DNA（基因）几乎（98-99%）相同，所
以接受进化论所说的“猿猴与人同宗”。
进化论者按他们所假设的“进化突变率”和“分子钟”来揣摩，估计从一个物种（
species）变成另一个物种经过的时间，例如：“猿猴演变成人类”是经过非常小的DNA
变化率，以及多代基因突变。可惜他们所假设的“进化突变率”包含许多不确定的因素
，所演算出来的年代也只是一个大概数字，如从“数万到几十万”年，差距很大，使人
无法分辨真假。许多如此这般的考古年代就这样出现在研究报告上，被报章、杂志、电
视、网路等大众媒体采用，以讹传讹，然后进一步变成学校教材。经年累月下来，猜想
和真相被混淆，人们就把这种多层次的“假想”当作“事实”。
自1990年庞大的跨国探索工程——人类基因计划（Human Genome Project），测定人类
染色体所包含DNA的30亿对碱基序列，从而绘制人类基因组图谱，破译人类遗传信息，
二十几年来又有许多新发现。人类各族群之间... 阅读全帖 |
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P******l
发帖数: 1648 | 40 从基因看人类的起源
文/张纪德
本文原发表于《中信》月刊总637期，由“中国信徒布道会”出版，蒙允许转载，特此
致谢。
在二十世纪，一般科学家都认为猿猴类与人类的DNA（基因）几乎（98-99%）相同，所
以接受进化论所说的“猿猴与人同宗”。
进化论者按他们所假设的“进化突变率”和“分子钟”来揣摩，估计从一个物种（
species）变成另一个物种经过的时间，例如：“猿猴演变成人类”是经过非常小的DNA
变化率，以及多代基因突变。可惜他们所假设的“进化突变率”包含许多不确定的因素
，所演算出来的年代也只是一个大概数字，如从“数万到几十万”年，差距很大，使人
无法分辨真假。许多如此这般的考古年代就这样出现在研究报告上，被报章、杂志、电
视、网路等大众媒体采用，以讹传讹，然后进一步变成学校教材。经年累月下来，猜想
和真相被混淆，人们就把这种多层次的“假想”当作“事实”。
自1990年庞大的跨国探索工程——人类基因计划（Human Genome Project），测定人类
染色体所包含DNA的30亿对碱基序列，从而绘制人类基因组图谱，破译人类遗传信息，
二十几年来又有许多新发现。人类各族群之间... 阅读全帖 |
|
M*****e
发帖数: 279 | 41 David Baltimore is sure one of the greatest scientists. He made contribution
to the understanding of the aberrant BCR-ABL that was later found to be the target of Gleevec by Brian Druker for the CML (leukemia).
CML patients (not all of them) have an unique chromosome (Philadelpha
chromosome) that is caused by the chromosomal translocations, resulting in the
constitutive activation of ABL kinase (a tyrosine kinase). |
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o********r
发帖数: 775 | 42 Review
Many different tumor types have polyclonal tumor origin: Evidence and
implications
Barbara L. ParsonsCorresponding Author Contact Information, a, E-mail The
Corresponding Author
aDivision of Genetic and Reproductive Toxicology, National Center for
Toxicological Research, HFT-120, 3900 NCTR Road, USFDA, Jefferson, AR 72079,
United States
Received 7 February 2008;
revised 14 May 2008;
accepted 15 May 2008.
Available online 31 May 2008.
Abstract
Few ideas have gained such strong acceptance i... 阅读全帖 |
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g*********d
发帖数: 233 | 43 据英国《每日邮报》1月7日报道，英国科学家找到了“急性癌症”的形成原因：细胞内
的染色体发
生“爆炸”破坏了DNA，从而让人有可能在短时间内患上癌症。相关论文发表于《细胞
》。
传统理论认为癌症是人体经历成千上万次的细胞突变后，慢慢演化的结果。但英国著名
的疾病研究机
构桑格研究所的新发现推翻了这种看法。这暗示了不管人们怎么努力保持身体健康，也
不能保证命运
不会拿他们开玩笑。同时还说明了为什么有些人在体检时根本没发现癌症痕迹，但数月
后突然就被诊
断患上这种疾病了。
桑格学院的科学家是通过研究750个肿瘤的遗传缺陷后得出以上结论的。其中大部分的
案例都与传统
理论相符，染色体的损坏是常年累积的结果。然而，其中至少有1/40的肿瘤不符合“标
准模式”，有的
染色体似乎是在一夜之间遭到破坏的。
参与此项研究的坎贝尔博士称：“测验结果太让我们惊讶了。在一个细胞里面，染色体
经过一次或者是
多次爆炸成为碎片。如果这个细胞开始笨拙地修补，把碎片杂乱的缝合起来，这样就破
坏了原来的
DNA结构，为癌症的快速形成提供了条件。”
坎贝尔博士表示：“这个细胞应该说‘好吧，我放弃’，而不是像对待昂贵的瓷... 阅读全帖 |
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n********k
发帖数: 2818 | 44 As you folks are discussing Cori, I happened to read his autobiography and
find it both interesting and enlightening:)))...BTW, it sounds Richard Axel
is a lot nicer than what I/we have heard...or in another word, his cruelty
is rooted in his obsession with science and indifference to humanity:))); As
well, it is pretty...he noted Cori but left his ex out...pretty human or
not human?
Autobiography
Richard AxelNew York City is my world. I was born in Brooklyn, the first
child of immigrant parents... 阅读全帖 |
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g*********d
发帖数: 233 | 45 Box 1. Properties of euchromatic and heterochromatic regions
Trying to define heterochromatin is like trying to define life itself: a
cluster of important properties can be specified, but there are exceptions
in every instance. For example, centromeres are usually associated with
blocks of flanking heterochromatin. However, the inner centromere of
Drosophila chromosomes is associated with blocks of nucleosomes that contain
CENP-A (also known as CID), a variant of histone H3, interspersed with
bl... 阅读全帖 |
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g******w
发帖数: 852 | 46 1.
Chromosome organization: new facts, new models
Miguel R. Branco , Ana Pombo
Trends in cell biology 2007; volume 17: issue 3
2.
Cell. 2012 Feb 3;148(3):458-72. Epub 2012 Jan 19.
Three-dimensional folding and functional organization principles of the
Drosophila genome.
Sexton T, Yaffe E, Kenigsberg E, Bantignies F, Leblanc B, Hoichman M,
Parrinello H, Tanay A, Cavalli G.
3.
Chromosome Res. 2006;14(5):477-95. Epub 2006 Jul 12.
Genome-wide scanning of HoxB1-associated loci in mouse ES cells using... 阅读全帖 |
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m**e
发帖数: 857 | 47 This is the most exciting part:
Theoretically the 44 chromosome man should have fewer problems having
children than his parents did. As this figure shows, there are no unpaired
chromosomes when he and a woman with 46 chromosomes have children. But all
of their kids would have a balanced translocation.
The chance is probably a 1 in 7 billion
However, I doubt the reality of this report.
The author (Barry Starr b****[email protected]) is the manager of Stanford at
The Tech, a program that trains Stanfo... 阅读全帖 |
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p*****c
发帖数: 20445 | 48 A-D E-K L-P R-Z
Peter Baumann, Ph.D.
HHMI Early Career Scientist
Stowers Institute for Medical Research
Peter Baumann’s research focuses on beginnings and endings: beginnings in
the form of reproduction in unisexual lizards and endings in the form of the
telomeres that protect chromosome tips.
Each time chromosomes are copied, telomeres—specialized stretches of DNA
that extend from the ends of each chromosome—become progressively shorter.
With each cell division, they ero... 阅读全帖 |
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