Human Heredity 7 v Karyotype v Single Genes

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Human Heredity 7 v Karyotype v Single Genes With Two Alleles v Single Genes

Human Heredity 7 v Karyotype v Single Genes With Two Alleles v Single Genes With Multiple Alleles v Sex-Linked Genes v X-Chromosome Inactivation

Definitions: Genome: the full set of genetic information that an organisms carries on it’s

Definitions: Genome: the full set of genetic information that an organisms carries on it’s DNA Karyotype: the complete set of chromosomes grouped together in pairs, arranged in order of decreasing size pairs 1 -22 = autosomes; pair 23 = sex chromosomes (XX = female, XY = male) – usually…

Male & Female Karyotypes: These pictures tell us two types of info: 1. If

Male & Female Karyotypes: These pictures tell us two types of info: 1. If we have the correct # of chromosomes 2. Gender

Lab: A Chromosome Study (Biology Corner) – cut out chromosomes & build one of

Lab: A Chromosome Study (Biology Corner) – cut out chromosomes & build one of two normal or 4 abnormal karyotypes Online Versions: Make A Karyotype - Learn Genetics University of Utah Karyotype Drag-and-Drop Activity

If we look closer at the chromosomes… we can see where traits are found

If we look closer at the chromosomes… we can see where traits are found review chromosomes: Chromosomes and Inheritance

Links to Chromosome Info: On your ipads: search chromosome image gallery (Chromosome Gallery (chromosomes,

Links to Chromosome Info: On your ipads: search chromosome image gallery (Chromosome Gallery (chromosomes, genes, traits & diseases)): http: //www. ornl. gov/sci/techresource s/Human_Genome/posters/chromoso me/chooser. shtml http: //ghr. nlm. nih. gov/chromosomes http: //www. ncbi. nlm. nih. gov/books/N BK 22266/

Human Genes controlled by one gene (letter) with a dominant or recessive allele Trait

Human Genes controlled by one gene (letter) with a dominant or recessive allele Trait Dominant Recessive Earlobe Attachment free attached Tongue Rolling cannot Cleft Chin cleft smooth Dimples have them do not Handedness right left Freckles yes no Naturally Curly Hair curly straight Hand Clasping left thumb over right thumb over left Hitch Hiker’s Thumb thumb straight bent thumb Bent Little Finger bent straight Hairline Shape widow’s peak straight hairline PTC Tasting taste cannot taste On to Multiple Alleles

http: //learn. genetics. utah. edu/content/begin/traits/

http: //learn. genetics. utah. edu/content/begin/traits/

http: //gslc. genetics. utah. edu

http: //gslc. genetics. utah. edu

http: //www. flickr. com/photos/munson/225270836/

http: //www. flickr. com/photos/munson/225270836/

http: //www. flickr. com/photos/timengstrom/5 08402553/

http: //www. flickr. com/photos/timengstrom/5 08402553/

http: //www. nps. k 12. nj. us/vailsburg/VMS%2 0 Human%20 Genetics/traits. htm

http: //www. nps. k 12. nj. us/vailsburg/VMS%2 0 Human%20 Genetics/traits. htm

http: //www. stratford. org/file. cfm? resourceid=2407&filename=Human Genetics. ppt

http: //www. stratford. org/file. cfm? resourceid=2407&filename=Human Genetics. ppt

Curly Straight http: //rds. yahoo. com/_ylt=A 0 WTbx. 7 FNRJUN 4 AVXSjzbk. F/SIG=122 hi

Curly Straight http: //rds. yahoo. com/_ylt=A 0 WTbx. 7 FNRJUN 4 AVXSjzbk. F/SIG=122 hi 1 k 2 o/EXP=1238722107/**http%3 A//www. flickr. com/photos/bfish/2833346448/

http: //gslc. genetics. utah. edu

http: //gslc. genetics. utah. edu

http: //mysite. verizon. net/vzepz 6 a 9/biorefwe b/phenotypeslab. html Hitchhiker's Thumb http: //www. ncrtec.

http: //mysite. verizon. net/vzepz 6 a 9/biorefwe b/phenotypeslab. html Hitchhiker's Thumb http: //www. ncrtec. org/tl/camp/gene/thumbs. htm Regular Thumb

 Having a bent little finger is a dominant trait http: //mysite. verizon. net/vzepz

Having a bent little finger is a dominant trait http: //mysite. verizon. net/vzepz 6 a 9/biorefweb/phenotypeslab. html http: //www. grisda. org/tstandish/teachers/presentations/General%20 Biology/Human%20 Genetics. ppt

www. autographedtoyou. com/. . . /butch_patrick 5. jpg www. thetech. org/. . . /images/ask/widows.

www. autographedtoyou. com/. . . /butch_patrick 5. jpg www. thetech. org/. . . /images/ask/widows. Peak. jpg

http: //gslc. genetics. utah. edu

http: //gslc. genetics. utah. edu

- Human Inheritance of Blood Type Blood type is determined by a single gene

- Human Inheritance of Blood Type Blood type is determined by a single gene with three alleles. This chart shows which combinations of alleles result in each blood type.

B. Multiple Alleles (more than one letter for a trait) (skin color & blood

B. Multiple Alleles (more than one letter for a trait) (skin color & blood types) blood type – three alleles: A, B or O A & B are both dominant, O is recessive Phenotype (blood type) A B Genotype(s) IAIA or IAi or (AA, AO) IBIB or IBi or AA, BB – homo AO, BO - hetero (BB, BO) AB IAIB or (AB) O ii or (OO) the importance of blood typing: during transfusions, incompatible blood types would result in clumping & death helpful in cases of disputed parentage

O O O OO OO B A A B AB AB 0 0 0

O O O OO OO B A A B AB AB 0 0 0 100 B O 25 25 A B 0 50 50 0 A B 0 25 25 50 A AB AO O BO OO O AO BO A B 100 0 AA AB AB BB

The Sex Chromosomes The sex chromosomes carry genes that determine whether a person is

The Sex Chromosomes The sex chromosomes carry genes that determine whether a person is male or female. They also carry genes that determine other traits.

the sex chromosomes the Y chromosome true

the sex chromosomes the Y chromosome true

X-chromosome Inactivation In females, most of the genes in one of the X chromosomes

X-chromosome Inactivation In females, most of the genes in one of the X chromosomes are inactivated (by super coiling into a structure known as a Barr Body) in each cell. **Example: calico cats – color of spots on fur is controlled by gene on X chromosome; spots are orange or black depending on which X chromosome is inactivated in different patches of skin.

The Sex Chromosomes

The Sex Chromosomes

C. Sex-linked Traits – traits carried on the sex chromosomes – usually the X

C. Sex-linked Traits – traits carried on the sex chromosomes – usually the X ** If X-linked: males pass on to daughters & not sons; females pass to daughter or son X-linked are usually recessive (all of your X’s must have it to show it) **If Y-linked (rare): males pass to sons; females neither pass nor are affected Females XX: XCXC – okay Males XY: XCXc – carrier XCY – okay Xc. Xc – has it Xc. Y – has it

Examples of Sex-Linked Inheritance 1. red-green color blindness: **more common in males since they

Examples of Sex-Linked Inheritance 1. red-green color blindness: **more common in males since they only have one X 2. hemophilia – blood doesn’t have the ability to clot properly – also X-linked recessive **studied in the family of Queen Victoria **can be treated with transfusions or injections of a clotting agent On To Slide 33 practice

Color blindness test http: //www. stratford. org/file. cfm? resourceid=2407&filename=Human Genetics. ppt

Color blindness test http: //www. stratford. org/file. cfm? resourceid=2407&filename=Human Genetics. ppt

Hemophilia Queen Victoria http: //www. stratford. org/file. cfm? resourceid=2407&filename=Human Genetics. ppt

Hemophilia Queen Victoria http: //www. stratford. org/file. cfm? resourceid=2407&filename=Human Genetics. ppt

- Human Inheritance Colorblindness Punnett Square Red-green colorblindness is a sex-linked trait. A girl

- Human Inheritance Colorblindness Punnett Square Red-green colorblindness is a sex-linked trait. A girl who receives only one recessive allele (written X c ) for red-green colorblindness will not have the trait. However, a boy who receives one recessive allele will be colorblind.

Hemophilia http: //www. stratford. org/file. cfm? resourceid=2407&filename=Human Genetics. ppt

Hemophilia http: //www. stratford. org/file. cfm? resourceid=2407&filename=Human Genetics. ppt

Trait is carried on a sex (X) chromosome Trait shown when on all X

Trait is carried on a sex (X) chromosome Trait shown when on all X chromosomes; males have a greater chances of having on all X chromosomes since they only have one X Xh. Y Xh Xh Xh. Xh Y Xh. Y X Xh. X XY Girls ½ Xh. Xh ½ Xh. X Boys ½ Xh. Y ½ XY Girls ½ hemophilia ½ normal Boys ½ hemophilia ½ normal XX Xb. Y X X Xb Xb. X Y XY XY Girls 100% Xb. X Boys 100% XY 100% normal; no bald children

Homework: Sex-linked Traits Worksheet - STEM Academy

Homework: Sex-linked Traits Worksheet - STEM Academy

Human Pedigrees A chart used to analyze the pattern of inheritance that shows the

Human Pedigrees A chart used to analyze the pattern of inheritance that shows the relationships in a family is a pedigree. Pedigrees can be used to determine the nature of genes and alleles associated with inherited human traits.

faculty. ccc. edu/jminarcik/Ch 5. ppt Standard Pedigree Symbols

faculty. ccc. edu/jminarcik/Ch 5. ppt Standard Pedigree Symbols

Autosomal = just big & little letters like old Mendelian genetics problems – no

Autosomal = just big & little letters like old Mendelian genetics problems – no X & Y faculty. ccc. edu/jminarcik/Ch 5. ppt DD or Dd dd

Autosomal = just big & little letters like old Mendelian genetics problems – no

Autosomal = just big & little letters like old Mendelian genetics problems – no X & Y rr RR faculty. ccc. edu/jminarcik/Ch 5. ppt Rr

Sex-linked = use X & Y since dominant & recessive genes are carried on

Sex-linked = use X & Y since dominant & recessive genes are carried on the X XR XR Xr Y XR Xr XR XR XR Y faculty. ccc. edu/jminarcik/Ch 5. ppt XR Xr

7 Pedigree Problems Whale Book My Sample Problems Frog Book

7 Pedigree Problems Whale Book My Sample Problems Frog Book

four the father 1 III Yes No III-8 and III-9

four the father 1 III Yes No III-8 and III-9

four The square stands for a tall male dog. It is half shaded because

four The square stands for a tall male dog. It is half shaded because the dog carries the recessive trait. the first male in generation II Four carry the short trait. Two are short.

The following questions refer to the pedigree shown for one type of deafness in

The following questions refer to the pedigree shown for one type of deafness in human beings. Squares symbolize males, circles females; filled symbols designate deaf individuals; open symbols individuals with normal hearing. 1. The genotype of individual 4 in generation I is probably a. D/D b. D/d c. d/d d. X D Y e. X d Y b. D/d 2. The genotype of individual 3 in generation IV is probably a. D/D b. D/d c. d/d b. D/d 3. This type of deafness is probably inherited as a. an autosomal dominant c. a sex-linked dominant b. an autosomal recessive d. a sex-linked recessive

recessive If it were dominant it could not show up in the F 3

recessive If it were dominant it could not show up in the F 3 generation unless at least one parent in the F 2 generation showed the trait dominant The female’s parent in the F 1 generation must be heterozygous dominant, or she could not have two children with the trait recessive carrier As a young woman needs two genes to be colorblind, the mother must have carried a gene for the trait

Genetic Disorders

Genetic Disorders

Mistakes in Meiosis 7 extra, missing or mixed up chromosomes

Mistakes in Meiosis 7 extra, missing or mixed up chromosomes

Autosomal Aneuploidy having an unusual number of chromosomes 1 -22 usually fatal Trisomy –

Autosomal Aneuploidy having an unusual number of chromosomes 1 -22 usually fatal Trisomy – have three of a particular autosome instead of just two results from nondisjunction (homologous chromosomes fail to separate) Examples: 1. trisomy 8 2. trisomy 13 (Patau syndrome) 3. trisomy 18 (Edward syndrome) 4. trisomy 21 (Down syndrome)

Trisomy 13 Patau’s Syndrome An individual with full trisomy 13 at age 7 years

Trisomy 13 Patau’s Syndrome An individual with full trisomy 13 at age 7 years (survival beyond the first year is uncommon). He is deaf and legally blind

Edward’s Syndrome trisomy-18 1/8000 live births Possible Malformations: * * * Back part of

Edward’s Syndrome trisomy-18 1/8000 live births Possible Malformations: * * * Back part of head may be prominent Short eyelids Small mouth and unusually small jaw A small head Fold of the eyelid in the lateral corner of the eye Low set malformed ears

Trisomy-21 Three chromosomes in the 21 st pair, and 47 total chromsomes Also called

Trisomy-21 Three chromosomes in the 21 st pair, and 47 total chromsomes Also called Down Syndrome Leads to physical defects and mental retardation http: //learn. genetics. ut ah. edu/content/disord ers/whataregd/down/i ndex. html

Trisomy 21 (Down Syndrome) Decreased muscle tone at birth Separated sutures (joints between the

Trisomy 21 (Down Syndrome) Decreased muscle tone at birth Separated sutures (joints between the bones of the skull) Asymmetrical or odd-shaped skull Round head with flat area at the back of the head Small skull Upward slanting eyes Small mouth with protruding tongue (see tongue problems) Broad short hands Single crease on the palm (see below) Retarded growth and development Delayed mental and social skills (mental retardation) http: //www. wayzata. k 12. mn. us/cms/images/stories/academics/7 t h%20 Grade/7%20 Blue%20 Science/genetics-human_gen. ppt

sex chromosome aneuploidy missing or extra sex chromosome(s) Examples: 1. Turner Syndrome - XO

sex chromosome aneuploidy missing or extra sex chromosome(s) Examples: 1. Turner Syndrome - XO females who lack ovaries & sex characteristics; short & sterile 2. Klinefelter Syndrome - XXY taller, longer limbs, sterile, some exhibit mental retardation 3. XYY male – 1 in every 1000; normal, fertile, taller than average

Turner Syndrome - XO http: //learn. genetics. utah. edu/content/disor ders/whataregd/turner/

Turner Syndrome - XO http: //learn. genetics. utah. edu/content/disor ders/whataregd/turner/

Klinefelter Syndrome - XXY http: //learn. genetics. utah. edu/content/disor ders/whataregd/klinefelter/

Klinefelter Syndrome - XXY http: //learn. genetics. utah. edu/content/disor ders/whataregd/klinefelter/

XYY male Two men, one taller than the other. (c) Dorling Kindersley

XYY male Two men, one taller than the other. (c) Dorling Kindersley

How to Study aneuploidy: take sample cells from fetus & photograph metaphase chromosomes –

How to Study aneuploidy: take sample cells from fetus & photograph metaphase chromosomes – line them up according to length & location of centromere = karyotype

A. Dominant Autosomal Heredity Huntington’s disease – a rare genetic disorder caused by a

A. Dominant Autosomal Heredity Huntington’s disease – a rare genetic disorder caused by a dominant gene progressive degeneration of the nervous system causes uncontrolled jerky movements & mental deterioration no effective treatment exists passed on because symptoms don’t occur until 30 -50, after they have children if you are at risk, you can find out if you are a carrier with a biochemical test http: //learn. genetics. utah. edu/content/disor ders/whataregd/hunt/index. html

B. Recessive Autosomal Heredity 7 most genetic disorders caused this way; rare except in

B. Recessive Autosomal Heredity 7 most genetic disorders caused this way; rare except in some ethnic groups

1. cystic fibrosis most common lethal genetic disorder among Americans 1 in 20 carry

1. cystic fibrosis most common lethal genetic disorder among Americans 1 in 20 carry the recessive allele; 1 in 2000 has it thick mucous in lungs makes breathing difficult; frequent lung infections thick mucous also slows the secretion of some digestive enzymes physical therapy, special diets, & new drug therapies have raised average life span http: //learn. genetics. utah. edu/content/disor ders/whataregd/cf/index. html

Physiotherapy for cystic fibrosis sufferer. (c) Dorling Kindersley

Physiotherapy for cystic fibrosis sufferer. (c) Dorling Kindersley

2. sickle-cell anemia a blood disorder most common in black Americans (Africa) or white

2. sickle-cell anemia a blood disorder most common in black Americans (Africa) or white Americans (Mediterranean Sea) red blood cells are shaped like a sickle or half moon – can clog blood vessels rbc’s have a shorter life span – people suffer from anemia hemoglobin protein in these cells differs from normal by one amino acid treatments include transfusions & drug therapy hetero’s can show signs if oxygen availability is low http: //learn. genetics. utah. edu/content/disor ders/whataregd/sicklecell/index. html

3. Tay-Sachs disease affects the nervous system missing an enzyme that normally breaks down

3. Tay-Sachs disease affects the nervous system missing an enzyme that normally breaks down a lipid produced & stored in the central nervous system & it accumulates in the cells results in blindness, progressive loss of movement & mental deterioration symptoms occur within the first year of life & result in death by age 5; no treatment allele common in PA Dutch http: //www. ncbi. nlm. nih. gov/pubmedhealth/PMH 0002390/

4. phenylketonuria is a treatable genetic disorder (Norway, Sweden) absence of an enzyme that

4. phenylketonuria is a treatable genetic disorder (Norway, Sweden) absence of an enzyme that converts one amino acid, phenylalanine, to tyrosine phenylalanine accumulates & can cause severe damage to the central nervous system newborns appear normal since mother’s normal enzyme level prevents accumulation, but when newborn begins drinking milk (high in phenylalanine) accumulation begins PKU tests are now preformed on all newborns a few days after birth to prevent retardation http: //learn. genetics. utah. edu/content/disor ders/whataregd/pku/index. html

Even More Genetic Disorders: 7

Even More Genetic Disorders: 7

Achondroplasia (dwarfism) Symptoms • Absent or delayed sexual development in an adolescent • Excessive

Achondroplasia (dwarfism) Symptoms • Absent or delayed sexual development in an adolescent • Excessive thirst with excessive urination • Headaches • Increased urine volume • Short stature -- below 5 th percentile on a standardized growth chart, an adult less than 5 feet tall • Slow growth before age 5 • Slowed or absent increase in height Short person with short limbs, with large head and prominent forehead. (c) Dorling Kindersley

Fragile X Syndrome Overview Fragile X syndrome is a genetic condition involving changes in

Fragile X Syndrome Overview Fragile X syndrome is a genetic condition involving changes in part of the X chromosome. It is the most common form of inherited mental retardation in males and a significant cause of mental retardation in females. Grey haired man with prominent chin. (c) Dorling Kindersley Symptoms • Mental retardation • Large testicles (macro-orchidism) after the beginning of puberty • Large body size • Tendency to avoid eye contact • Hyperactive behavior • Large forehead or ears with a prominent jaw

Albinism is a congenital absence of normal pigmentation. It is characterized by partial or

Albinism is a congenital absence of normal pigmentation. It is characterized by partial or total lack of melanin pigment in the eyes, skin and hair. People who have this condition have visual difficulties like hypersensitivity to bright light and glare and many others.

Galactosemia http: //learn. genetics. utah. edu/content/disor ders/whataregd/galactosemia/index. html

Galactosemia http: //learn. genetics. utah. edu/content/disor ders/whataregd/galactosemia/index. html

Cri-du-Chat Symptoms • Cry that is high-pitched and sounds like a cat • Downward

Cri-du-Chat Symptoms • Cry that is high-pitched and sounds like a cat • Downward slant to the eyes • Low birth weight and slow growth • Low-set or abnormally shaped ears • Mental retardation • Partial webbing or fusing of fingers or toes • Single line in the palm of the hand (simian crease) • Skin tags just in front of the ear • Slow or incomplete development of motor skills • Small head (microcephaly) • Small jaw (micrognathia) • Wide-set eyes http: //learn. genetics. utah. edu/content/disor ders/whataregd/cdc/index. html

Williams Syndrome Williams syndrome is a rare genetic disorder that can lead to problems

Williams Syndrome Williams syndrome is a rare genetic disorder that can lead to problems with development • affects a child's growth, physical appearance, and cognitive development • missing genetic material from chromosome 7, including the gene elastin gives blood vessels the stretchiness and strength • The most common symptoms of Williams syndrome are mental retardation, heart defects, and unusual facial features (small upturned nose, wide mouth, full lips, small chin, widely spaced teeth). • People with this syndrome also exhibit characteristic behaviors, such as http: //learn. genetics. utah. edu/content/di hypersensitivity to loud noises and an sorders/whataregd/williams/index. html overly outgoing personality.

Resources: http: //www. biology. iupui. edu/biocourses/N 1 00/humgenetics 2. html http: //biologyexams 4 u.

Resources: http: //www. biology. iupui. edu/biocourses/N 1 00/humgenetics 2. html http: //biologyexams 4 u. blogspot. com/2012/0 3/human-genetic-disorder-part-i. html http: //www. warrenhills. org/Page/4382 Genetic Disorders narragansett. k 12. ri. us/NHS Power. Point Genetic Disorders faculty. ccc. edu/jminarcik/Ch 5. ppt