Genetics and longevity
Download
1 / 12

Genetics and Longevity - PowerPoint PPT Presentation


  • 351 Views
  • Updated On :

Genetics and Longevity. Human Studies. Genealogical Studies. Bell - 1918 Descendents of William Hyde (died 1681) n = 8,798 correlation between parental longevity and offspring longevity greater influence of father ?. Yuan - 1932 Chinese family 1365-1849 (n = 7,500).

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Genetics and Longevity' - richard_edik


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Genetics and longevity l.jpg

Genetics and Longevity

Human Studies


Genealogical studies l.jpg
Genealogical Studies

Bell - 1918

Descendents of William Hyde (died 1681)

n = 8,798

correlation between parental longevity and

offspring longevity

greater influence of father ?


Yuan 1932 chinese family 1365 1849 n 7 500 l.jpg
Yuan - 1932 Chinese family 1365-1849 (n = 7,500)


Slide4 l.jpg

Jalavisto (1951) – 12,876 Scandinavians (1500-1829)

maternal longevity better predictor

Mayer (1991) - New England 1578-1963

n = 14,549, 6 families

what portion of longevity is genetically inherited ?

Does this value change over time ?

95% confidence limits 0.10 -0.33 (10-33%)

heritability

does not change with time


Population studies l.jpg
Population Studies

Actuarial Studies -

parental age has affect on length of life of offspring

father longevity better predictor

details of ind. Studies vary slightly, but overall trend is clear


Twin studies l.jpg
Twin studies

Not all familial effects are genetic

twin studies can sort this out

Kallman 1957 -

1739 pairs of twins

at least one twin > 60

effects of parental life span as well as

similarity between twins

fraternal vs. identical

Correlation between parental span and offspring


Twins l.jpg
Twins

Avg. difference between fraternal twins = 6 years

for same sex twins, 9 years for diff. Sex

Identical Twins - 3 year diff.

Heritability - 0.33 to 0.5

Heredity is an important factor determining life span

What we inherit is the absence of a tendency for a

short life

Biomarkers a better measure of age related changes ?

Genetic vs. Environmental Control


Gender differences l.jpg
Gender Differences

Stronger Sex ??


Gender gap l.jpg
Gender Gap

Differential Mortality: Changes Sex Ratio

At conception 170:100 (est.)

End 1st Trimester 130:100

At Birth 106:100

Adolescence 100:100

Age 75 60:100

Why ?

Genetics ? Biology ? Behavior ? Environment ?


Gender gap10 l.jpg
Gender Gap

Y-Chromosome-

78 genes, all but 18 directly involved with

spermatogenesis (sperm production)

Single Y Chromosome-

no chance for

genetic recombination

“Proband” males (partial deletion

of Y chromosome)

82.4 years vs. 77.4 for females

(in same family)


Gender gap11 l.jpg
Gender Gap

Role of androgens ? (testosterone)

eunuchs (postpubertal castration)

live longer than controls

Physiology vs. Behavior ??

Testosterone given to female mice

lowers their immune response

Protective effects of estrogen in coronary artery disease

Waldron 1987 - 18 % of gap due to hormone diff.

55% due destructive behaviors

Smoking, guns, cars, alcohol


Gender gap12 l.jpg
Gender Gap

In U.S. Gender Gap has doubled since 1900

(argues against biological/genetic explanation)

Other ethnic/ cultural / societal groups

Gap varies (10 years to -2.8)

Males live longer in 6/157 populations

general high rate of premature death

mortality of childbirth

female infanticide

Other animal species - males live longer in some


ad