Post on 05-Jan-2016
Beginning of the chapterLactose intolerance and genetics (Lactose
Sensor)
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SENSORS
LACTOSE SENSOR
Lactose intolerance
GENETICS
Lactose (in)tolerance
GALGAL
GLUGLU
LACTOSE
Lactase geneLactase gene
GLUGLU
GALGAL
Lactose cannot be directly Lactose cannot be directly absorbed in the intestineabsorbed in the intestine
The lactase enzyme breaks down The lactase enzyme breaks down lactose into smaller partslactose into smaller parts
GalactoseGalactose
GlucoseGlucose
GENETICS
GALGAL
GLUGLU
LACTOSE
Lactase geneLactase gene
GLUGLU
GALGAL
LACTOSE
Age++Age++
Lactose (in)tolerance
GENETICS
Moderate symptoms
Severe symptoms
Mild symptoms
Lact
ase
enzy
me
Lact
ase
enzy
me
Age (years)Age (years)10 20 30 40 50 60 7010 20 30 40 50 60 70
1 of 6 people: the lactase enzyme 1 of 6 people: the lactase enzyme is gradually switched offis gradually switched off
Lactose intoleranceLactose intolerance
Lactose (in)tolerance
GENETICS
GALGAL
GLUGLU
LACTOSE
Lactase geneLactase gene
GLUGLU
GALGAL
LACTOSE
Age++Age++
SNP
Lactose (in)tolerance
GENETICS
Moderate symptoms
Severe symptoms
Mild symptoms
Lact
ase
Lact
ase
enzy
me
enzy
me
Age (years)Age (years)10 20 30 40 50 60 7010 20 30 40 50 60 70
5 of 6 people: the lactase enzyme is constantly produced5 of 6 people: the lactase enzyme is constantly produced
1 of 6 people: the lactose enzyme 1 of 6 people: the lactose enzyme is gradually switched offis gradually switched off
Lactose intoleranceLactose intolerance
Lactose (in)tolerance
GENETICS
Lactose (in)tolerance
Genetic variation Genetic variation originated in an originated in an
EuropeanEuropean
GENETICS
Lactose (in)tolerance
Shortage of food Shortage of food caused the death caused the death of many peopleof many people
GENETICS
Lactose (in)tolerance
Milk as an Milk as an additional food additional food
source = source = survival survival advantageadvantage
GENETICS
Lactose (in)tolerance
Lactose tolerantLactose tolerant
Lactose Lactose intolerantintolerant
GENETICS
Lactose (in)tolerance
Lactose tolerantLactose tolerant
Lactose Lactose intolerantintolerant
LACTOSE SENSORVarious forms of
lactose intolerance
Lactase geneLactase geneAge++Age++
Primary lactose intolerance20% of people Occurs with increasing age
Secondary lactose intoleranceAcquired (non-genetic) Disease / intestinal damage
Congenital lactose intoleranceGenetic variation in the lactase geneVery rareOccurs in newborns
Milk protein allergy3% of babies
GLUGLU
GALGAL
Lactase geneLactase geneAge++Age++
LACTOSE SENSOR
What is the relationship between age and lactose intolerance?
0 1 5 16 30 50 80 0 1 5 16 30 50 80
PRIMARYPRIMARY
CongenitalCongenital
SECONDARY LACTOSE INTOLERANCESECONDARY LACTOSE INTOLERANCE
MILK ALLERGYMILK ALLERGY
BABY SensorBABY Sensor
LACTOSE SENSORLACTOSE SENSOR
ALLERGY SENSORALLERGY SENSOR
Standard lactose intolerance (breath) testStandard lactose intolerance (breath) test
End of the chapterLactose intolerance and genetics
(Lactose Sensor)
47