알코올의 태아에 미치는 영향에 관한 알코올의 태아에 미치는 영향에 관한 후성유전학적 기전 연구후성유전학적 기전 연구

유전학연구실 유전학연구실 이봄이이봄이

Cheil General Hospital & Women’s Healthcare CenterCheil General Hospital & Women’s Healthcare CenterLaboratory of Medical GeneticsLaboratory of Medical Genetics

Cheil General Hospital & Women’s Healthcare CenterCheil General Hospital & Women’s Healthcare CenterLaboratory of Medical GeneticsLaboratory of Medical Genetics

Cheil General Hospital & Women’s Healthcare CenterCheil General Hospital & Women’s Healthcare CenterLaboratory of Medical GeneticsLaboratory of Medical Genetics

• Studies on changes in gene expression that are

NOTNOT caused by changes in the sequence of DNA

• The mitotically and meiotically heritable control of

gene expression not related to DNA sequence

during development

Beyond the DNA Sequence!Beyond the DNA Sequence!

EpigenomeEpigenome

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Heritable Heritable silencingsilencing

Interaction of heritable silencingInteraction of heritable silencing

•Small RNA mediated ControlSmall RNA mediated Control

•Post-translation modificationPost-translation modification •CpG islandCpG island

•Chromatin condensationChromatin condensation

Gene “switched OFF”Gene “switched OFF”• Silent (condensed) chromatin

• Methylated cytosines (red circles)

• Deacetylated histones

Gene “switched ON”Gene “switched ON”• Active (open) chromatin

• unmethylated cytosines (white circles)

• Acetylated histones

• The most heavily studied mode of epigenetic regulation

• By one of a variety of DNA methyltransferases (DNMTs) responsible for adding a methyl group to cytosine residues in cytosine/guanine- rich regions of DNA (called ‘CpG islands’)

CpG islandsCpG islands

• In and near approx. 40% of promoters of mammalian genes.

• About 70% of human promoters have a high CpG content.

• The “p” in CpG - phosphodiester bond between the cytosine and the guanine.

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• Classic Teratogen affecting to reduce growth factor levels

- genetic, biochemical, cellular, and morphological

• Interferes

- DNA methylation

- histone modification

- noncoding RNA

• Dosage and timing – inducing target organ developmental

defect

During PregnancyDuring Pregnancy

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• differences in timing and dosage underline this variability

• preconception, preimplantation, and gastrulation

• In Rat, placental mRNAs is altered after moderate drinking

during pregnancy

• Exposure to alcohol in the embryonic mouse can lead to

structural and neurophysiologic changes.

• Preconceptional effects mediated by paternal and maternal

alcohol consumption

Studies in the Animal ModelsStudies in the Animal Models

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• General assessment about fetal development

• Limited human tissue specimen

• Partially researched on tissue specific epigenetic study

- Genome-wide methylation study via microarray

• Rarely challenged to elucidate the relation of epigenetic

changes within a family

Studies In Human Studies In Human

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임신중 알코올 노출 임신부 및 태아 (n=100) vs

대조군 ( 임신중 알코올 비노출 임신부 및 태아 ) (n=100)

태아 알코올 증후군 및 알코올 대사 관련 대상유전자 선별

대상유전자 프로모터 부위 메틸화 양상 분석모체 : 노출 시기별 채혈

태아 : 출생 시 태반과 제대혈

태아 발달 평가임신중 태아 및 출생 후 발달 사항

자연유산 , 기형 , 조산 및 저체중증

기본정보수집 임신 초 , 중 , 말기 알코올 노출 기간 ,

빈도 , 음주량 , 기타 (흡연 , 약물 )

생체바이오마커 측정법 이용임신중 알코올 노출 시기별 모체의 알코올 노출력 평가

생체바이오마커 측정법 이용 출생 시 태변에서 FAEEs 측정

임신전 알코올 노출 배우자 및 태아 (n=100)vs

대조군 ( 임신전 알코올 비노출 배우자 및 태아 ) (n=100)

태아 알코올 증후군 및 알코올 대사 관련 대상유전자 선별

대상유전자 프로모터 부위 메틸화 양상 분석부체 : 노출 정도별 채혈

태아 : 출생 시 태반과 제대혈

태아 발달 평가임신중 태아 및 출생 후 발달 사항

자연유산 , 기형 , 조산 및 저체중증

기본정보수집 알코올 노출 기간 , 임신전 금주기간

빈도 , 음주량 , 기타 (흡연 , 약물 )

부체의 정액 검사정자수형태운동성

• Methylation pattern analysis - A genome-wide methylation analysis - micro array - Bisulfited genomic sequencing - Methylation-sensitive restriction enzyme - Gel electrophoresis analysis / fragment analysis

• Target Gene expression level analysis : - Quantitative Real-time PCR

• Candidate Target Gene : - Alcohol metabolism related genes ; ALDH2 (aldehyde dehydrogenase 2 family) , ADH1B (alcohol dehydrogenase 1B

(class I)

- Imprinting genes, Developmental related genes etc. ; H19 etc. - ADHD (attention-deficit hyperactivity disorder) related genes ; dopamine transporter gene, norepinephrine transporter gene

- DNA Methylation related regulating genes ; DNMT (DNA methyltransferase), MECP2 (methyl CpG-binding protein 2)

- Plasma homocysteine ; HERP (Homocysteine-induced ER protein)

methylationunmethylation

Restrictionenzyme

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