《医学遗传学》课程PPT教学课件（留学生 Medical Genetics）06 Chapter Multifactorial Disease

Medical Genetics Multifactorial Disease

Multifactorial Disease Medical Genetics

Emphasis Qualitative trait Quantitative trait Characteristics of Polygenic Inheritance *Threshold Theory *Heritability Estimate of Heritability 必 Inheritance Characteristics of Polygenic Disease Estimate of Recurrence Risk

❖ Qualitative trait & Quantitative trait ❖ Characteristics of Polygenic Inheritance ❖ Threshold Theory ❖ Heritability & Estimate of Heritability ❖ Inheritance Characteristics of Polygenic Disease ❖ Estimate of Recurrence Risk Emphasis

Major gene Minor gene Additive effect Additive gene Polygenic inheritance Multifactorial inheritance Multifactorial traits are those which result from an interaction between multiple genes and often multiple environmental factors

Major gene & Minor gene Additive effect & Additive gene Polygenic inheritance Multifactorial inheritance Multifactorial traits are those which result from an interaction between multiple genes and often multiple environmentalfactors

Qualitative Trait Monogenic t女ait 120cm 165cm aa AA OR Aa Height of pituitary dwarfism normal

Qualitative Trait Monogenic trait 120 cm 165 cm aa AA OR Aa Height of pituitary dwarfism & normal

Qualitative Trait Monogenic trait 05% 4550% 100% aa Aa AA PAH activity of PKU carrier normal

Qualitative Trait Monogenic trait 0~5 % 45~50 % 100 % aa Aa AA PAH activity of PKU、carrier & normal

Qualitative Trait Qualitative trait:genetic traits which are present or absent.One has the trait or not. 爱

Qualitative Trait Qualitative trait: genetic traits which are present or absent. One has the trait or not

Quantitative Trait Qualitative trait Quantitative trait:genetic traits which are measurable characteristics

Quantitative Trait Qualitative trait Quantitative trait: genetic traits which are measurable characteristics

Quantitative Trait 00157722252627171117441 4'10"411"5'0"515'2”53”5'4"5'5”56"57"5'8”5'95'105'11“60”6'1"62

Quantitative Trait

Quantitative Trait Qualitative trait Quantitative trait 80 Gaussian distribution K!qBLIeA 0900200 the bell-shaped curve 130 140150160170180190200 Height (cm)

130 140 150 160 170 180 190 200 Height (cm) 80 70 60 50 40 30 20 10 Variability Gaussian distribution the bell-shaped curve Quantitative Trait Qualitative trait Quantitative trait

Quantitative Trait the tallest the shortest AABB AAB'B F the median AA'BB AB AB AB AB AB AABB AABB AABB AA'BB AB AABB AABB AA'BB' AA'B'B' AB AABB AABB AABB AA'BB AB AA'BB AA'BB' A'A'BB' AABB

P the tallest the shortest AABB A’A’B’B’ F1 the median AA’BB’ F2 AB AB’ A’B A’B’ AB AABB AABB’ AA’BB AA’BB’ AB’ AABB’ AAB’B’ AA’BB’ AA’B’B’ A’B AA’BB AA’BB’ A’A’BB A’A’BB’ A’B’ AA’BB’ AA’B’B’ A’A’BB’ A’A’B’B’ Quantitative Trait