Bài 21. Di truyền y học

BIRTH DEFECTS
BÀI 12
DI TRUYỀN Y HỌC
( DÒNG DÕI VỚI NHỮNG KHIẾM KHUYẾT ? )
Cellular Basis of Cancer
Tế bào cơ bản gây ung thư
What causes Cancer?
Nguyên nhân gây ung thư là gì?
( Có thể do chất hóa học,vius hoặc vi khuẩn,có thể do bức xạ)
Hanahan and Weinberg, Cell 100: 57, 2000
Apoptosis
Oncogenes
Tumor Suppressor
Inv. and Mets
Angiogenesis
Cell cycle
Một số con đường gây ung thư
CANCER AND GENETICS
UNG THƯ VÀ DI TRUYỀN
Cancer: genome disease( Ung thư: Bệnh do gen)
Causes of genomic changes(Nguyên nhân của gen thay đổi)
Effects of genomic changes( Tác động của thay đổi gen)
Chromosomal changes in the genome of cancer cells: tip of the iceberg
(NST thay đổi trong bộ gen của tế bào ung thư: xuất phát tiềm ẩn lớn)
Terminal
Deletion
http://www.tokyo-med.ac.jp/genet/cai-e.htm
Ring
Chromosome
Robertsonian
Translocation
Deletion
Reciprocal
translocation
Isochromosomes
Insertion
Inversion
Duplication
Tế bào hình lưỡi liềm
Polymers of hemoglobin
deform red blood cells
Normal
Sickle
Sickle Cell Anemia...
NORMAL ABNORMAL
Named after this cutting tool… a sickle.
Tế bào hồng cầu thường
Tế bào hồng cầu hình lưỡi liềm
Tế bào ung thư
Tế bào ung thư

Tạo giao tử của cá thể XX
c. XYY individuals are male, and tend to be taller than average. Fertility is sometimes affected.
d. XXX individuals are usually normal women, although they may be slightly less fertile and a few have below average intelligence.
e. Higher numbers of X and/or Y chromosomes are sometimes found, including XXXY, XXXXY, and XXYY. The effects are similar to Klinefelter syndrome. Consequences of sex chromosome aneuploidy in humans are summarized in Table 11.2.
Biểu hiện của người có NST giới tính
không bình thường
Ảnh hưởng của NST giới tính tới cơ thể
Chiếm
(0.1 % )
Chiếm
0.02 %
Chiếm (0.1%)
Evidence for the Y Chromosome Mechanism of Sex Determination
Bằng chứng tác động của NST giới tính Y

1. Understanding of the Y chromosome mechanism of sex determination came from the study of individuals with unusual chromosome complements. In humans these aneuploidies include:
a. XO individuals, who are sterile females exhibiting Turner syndrome. Most XO fetuses die before birth. Surviving Turner syndrome individuals become noticeable at puberty, when secondary sexual characteristics fail to develop. Other traits include:
i. Below average height.
ii. Weblike necks.
iii. Poorly developed breasts.
iv. Immature internal sexual organs.
v. Reduced ability to interpret spatial relationships.
Hội chứng XO Turner
Features:
Female phenotype
Short stature
Webbing of the neck
Small, widely-spaced nipples
Juvenile sexual development

b. XXY individuals, who are male and have Klinefelter syndrome. Other traits include:
i. Above average height.
ii. Breast development in about 50% of XXY individuals.
iii. Subnormal intelligence in some cases.

Hội chứng Klinefelter
XXY_ Hội chứng Klinefelter
Male
Often unusually tall; long arms and legs
Breast development
“Hairy Pinna Syndrome” Hội chứng chùm lông trên tai
Hội chưng Đao
Cleft Palate...
Clefts often involve the lip, the roof of the mouth (hard palate) or the soft tissue in the back of the mouth (soft palate).
During the first trimester of pregnancy the two sides of the mouth and lip area grow together. A combination of genetic and environmental factors sometimes interfere with this development, and a cleft results.
Nứt môi hở hàm ếch
Hemangioma...
The vast majority of hemangiomas fall into the category of port-wine stains or small “birthmarks”, with only 15% being of the tumor variety or needing medical intervention.
Hemangioma...
Hemangioma...
To remove some protruding hemangiomas surgically would result in bleeding to death. As the blood vessels in the area die, part or all of the mass can be removed. Laser surgery has been extremely effective for hemangiomas…even removal of the “stain” variety.
Club Foot...
Club foot is a birth defect of the foot and ankle. It can occur in one or both feet. Advances in medicine have been useful in the surgical correction of problems. This defect occurs in the first trimester of pregnancy… during formation.
Chân khèo
Dwarfism...
Dwarfism is a genetic/genetic linked disorder. All forms of dwarfism are characterized by small stature. The overwhelming majority of these individuals enjoy normal intelligence, normal life spans, and reasonably good health. Medical problems are often linked to orthopedic complications.
In most forms of dwarfism, only the long bones are shortened. This produces a body image that is quite disproportionate. Dwarfs, men and women, rarely grow over 4’ 10” tall.
Nguyên nhân gây còi cọc
Examples of Autosomal Dominant Disorders
Ví dụ một số bệnh do NST
Dwarfism
Polydactyly and Syndactyly
Hypertension
Hereditary Edema


Chronic Simple Glaucoma – Drainage system for fluid in the eye does not work and pressure builds up, leading to damage of the optic nerve which can result in blindness.
Huntington’s Disease – Nervous system degeneration resulting in certain and early death. Onset in middle age.
Neurofibromatosis – Benign tumors in skin or deeper
Familial Hypercholesterolemia – High blood cholesterol and propensity for heart disease
Progeria – Drastic premature aging, rare, die by age 13. Symptoms include limited growth, alopecia, small face and jaw, wrinkled skin, atherosclerosis, and cardiovascular problems but mental development not affected.
Examples of Autosomal Recessive Disorders
Ví dụ một số bệnh do NST
Congenital Deafness
Diabetes Mellitus
Sickle Cell anemia
Albinism
Phenylketoneuria (PKU) – Inability to break down the amino acid phenylalanine. Requires elimination of this amino acid from the diet or results in serious mental retardation.


Galactosemia – enlarged liver, kidney failure, brain and eye damage because can’t digest milk sugar
Cystic Fibrosis – affects mucus and sweat glands, thick mucus in lungs and digestive tract that interferes with gas exchange, lethal.
Tay Sachs Disease – Nervous system destruction due to lack of enzyme needed to break down lipids necessary for normal brain function. Early onset and common in Ashkenazi Jews; results in blindness, seizures, paralysis, and early death.
Constitutional cytogenetic abnormalities
Thể trạng di truyền tế bào không ổn định
Robertsonian translocation; 45,XX,rob(13,14)
Constitutional cytogenetic abnormalities
Thể trạng di truyền tế bào không ổn định
Trisomy 21; 47,XX,+21

Constitutional cytogenetic abnormalities
Thể trạng di truyền tế bào không ổn định
DiGeorge Syndrome; chromosome 22 deletion
Acquired cytogenetic abnormalities
Thể trạng di truyền tế bào không ổn định
Philadelphia chromosome; 46,XX,t(9,22)
Acquired cytogenetic abnormalities
Thể trạng di truyền tế bào không ổn định
Inversion 16; 46,XY,inv(16)