brief history of genetics Flashcards
molecular genetics
1) chemical bases of heredity
- genomics - study of genes
- proteomics - study of proteins
cytogenetics
1) physical basis of herefity
behavior genetics
1) how a certain organism behave
population genetics
1) transmission of trait in a large group of individual through time
classical genetics
how traits are transmitted
gregor mendel
1) 150 years ago, genotype results in phenotype
human genome project
1) new tool for diagnostics and prognosis
why genetics?
1) to understand etiology
- for diagnosis, treatment plan, prevention, understand diseases
- implement personalized medicine
development of the head and face
1) coordinated by TFs and signaling molecules
- 4th week of gestation
- migration of neural crest cells establishing facial primordia
- maxillary prominences enlarge and grow toward each other and nasal processes
craniofacial and upper airway structures
1) mesenchymal and epithelial tissues are synchronized
- interruption of TFs and GFs leads to congenital anomalies
2) week 4
-64 upregulated genes
3) 5 weeks
- 26 upregulated genes in frontonasal process
4) 6th week
- lateral nasal prominence 45 genes
- medial nasal prominence 36 genes
most important genes in craniofacial morphogenesis
1) polarizing signals
2) growth factors
3) cell adhesion molecules
4) ECM
asking about disorders
1) what does this boy have
2) was he born like this
- yes, congenital anomaly
3) does he look like somebody in the family
- heredity
4) how this happened
- etiology
5) when this happened
- prenatal development
history of genetics
1) pre-mendelian era
- 19th century
- 1875 Darwin identified hereditary anodontia
2) classical era
- 1900-1930
3) DNA era
-1930-1970
- heredity vs environment
4) genomic era
- 1970-2010
- heritability era
5) postgenomic era
-2010-
- postgenomic and epigenomic period
- precision medicine period
aristotle
1) homunculus
- carries a tiny version of adult, each part of which can be expanded into the corresponding part of adult
2) preformation
- pre-formed bodies, sperm cells
gregor mendel
1) 1822-1884
2) law of uniformity
- two homozygotes with different alleles are crossed and produce same offspring in F1
2) law of segregation
- each characteristic is represented by two genes, only one which is transmitted at a time
3) law of independent assortment
- members of different gene pairs segregate to offspring independently of one another
charles darwin
1) 1809-1882
2) all species have descended from common ancestry
3) branching pattern of evolution from natural selection
4) theory of evolution in “the origin of species”
friedrich mischer
1) 1844-1895
2) discovered new type of weak acid abundant in the nuclei of the WBC that was DNA
1900 three scientists
1) 34 years after mendel, rediscovered mendel laws
2) erich von tschermak, hugo de vries, carl correns
walter sutton
1) 1877-1916
2) behavior of chromosomes
- applies mendenlian laws to cellular level
- significant contribution to moden biology
thomas hunt morgan
1) 1866-1945
2) fruit flied to confirm that genes were located on the chromosomes
3) sturtevant was the first scientist who created a genetic map of a fruit fly
william bateson
1)1861-1926
2) first one to use the term genetics, allele, zygote, heterozygote, homozygote
archibald garrod
1) 1857-1936
2) studied families with alcaptonuria
- autosomal recessive
- extrapolated mendelian laws
1944 3 scientists
1) avery, macleod, and mccarty
2) showed DNA can transform properties of cells
- chemical nature of genes
3) streptococcus pneumoniae
rosalind elsie franklin
1) 1920-1958
2) xray diffraction photo of DNA
3) crucial clues to the structure of DNA 4)
watson and crick
1) 1953
2) discovered the double helical structure of DNA
3) received nobel prize
classification of genetic disease
1) single gene defects / mendelian disorders
2) multifactorial or polygenetic
3) cytogenetic
4) atypical pattern of inheritance
mendelian inheritance
1) single gene disorder
2) single mutation in structure of DNA
- cause single basic defect with pathological consequences
3) autosomal dominant
- 50% offspring
4) autosomal recessive
- 25% offspring
5) x-linked recessive
- 50% sons
- 50% daughters carriers
victor mckusick and robert gorlin
1) victor mckusick
- mckusick catalog
- online mendelian inheritance in man
- 1921-2008
2) robert gorlin
- syndromes of head and neck
- 1923-2006
by 1966
1) 1500 single gene disorders identified by mckusick
by 1998
1) 12the edition of the catalog, 8500 entried
by august 2016
1) 23,600 entries
DNA sequencing
1) 1918-2013
2) frederick sanger
jumping genes
1) 1902-1992
2) barbara mcclintock
triplet genetic code
1) 1927-2010
2) marshall warren nirenberg
how face develops in treacher collins
1) lower and midface stays behind in growth
2) upper face will overgrow
3) must start early in the treatment of the ramus of the mandible
- to deal with midface hypoplasia
4) eyes should be corrected as well
- closure for function
5) things need to be done at a certain time
how will this help me with care an treatment of my patient
1) understand gene functions
- know which areas of the face will stay behind the others in growth
2) early intervention
- with distraction osteogenesis will prevent progression of dysmorphology due to slow growth of affected part and normal growth of other areas
