Pratique du Shadowing: High Resolution Melting (HRM) analysis made easy. - Apprendre l'anglais à l'oral avec la vidéo

Création de la leçon...
1
High resolution melting
2
or HRM is a very sensitive method to detect sequence variation
3
in different samples up to a resolution of a single base pair without the need of sequencing.
4
Here you see a wild type of DNA or a PCR product.
5
After mutation you may get a homozygous mutant in
6
which both the alleles are mutated or a heterozygous mutant in which a single allele is mutated.
7
Now you want to check if mutation is there or not.
8
HRM is based upon the principle of DNA dissociation with increase in temperature followed by detection by a fluorescent dye.
9
The DNA denituration is based on the GC content.
10
Higher the GC content, stronger will be the DNA bonds and higher will be the melting temperature to dissociate the two strands.
11
In HRM, the detection is assisted by specific binding of a saturating fluorescent dye to the double-stranded DNA
12
and measuring its fluorescence in real time on increasing the temperature gradually.
13
For HRM, you need to PCR amplify your target gene locus to obtain a specific amplicon.
14
Smaller the size of amplicon, better the results will be.
15
Then you add a saturating fluorescent dye
16
that binds to the dna only in the double stranded form
17
then you proceed for hrm analysis in a real time machine here you gradually increase the temperature
18
and fluorescence is measured simultaneously the plot shows fluorescence in the y-axis and temperature on the x-axis
19
3 different curves are obtained for wild, homozygous and heterozygous mutant.
20
Here you see as homozygous mutant had a GC mutation as seen in the previous slide its TM is higher.
21
So the curve shifts towards the right.
22
Heterozygous mutant on the other hand have a mutation in only one strand.
23
So it has a base mismatch and hence the TM is reduced and the curve shifts towards the left.
24
method is so sensitive that it detects the variation in the melting temperature up to 0.2 degree Celsius.
25
HRM being a simple, economic, rapid and precise method of DNA variant detection, it can be used for mutant identification,
26
SNP genotyping, DNA methylation by bisulfide sequencing, DNA fingerprinting and so on.
27
This video has been made on a special request by Ms. Sahily Russell.
✨ Vidéo recommandée
The different types of mutations | Biomolecules | MCAT | Khan AcademyC1
2
41 phrases

The different types of mutations | Biomolecules | MCAT | Khan Academy

IELTS PrepTOEFL PrepUniversity Students
SOFI: Sequence-based, cross-sectoral, One-health surveillance of food-borne infections | IMMEM XIVC1
1
83 phrases

SOFI: Sequence-based, cross-sectoral, One-health surveillance of food-borne infections | IMMEM XIV

IELTS PrepTOEFL PrepUniversity Students
Human Immortality 4K | Can Science Defeat Aging?C1
2
530 phrases

Human Immortality 4K | Can Science Defeat Aging?

IELTS PrepTOEFL PrepUniversity Students
Muỗi thích cắn ai hơn? | TedEd | Tiếng Anh song ngữ #shorts #tienganh #teded #hoctienganh #englishC1
13
18 phrases

Muỗi thích cắn ai hơn? | TedEd | Tiếng Anh song ngữ #shorts #tienganh #teded #hoctienganh #english

IELTS PrepTOEFL PrepUniversity Students
What is it? A young boy with deafness and twisting limb movementsC1
3
148 phrases

What is it? A young boy with deafness and twisting limb movements

IELTS PrepTOEFL PrepUniversity Students
Helge Ewers SeminarC1
1
680 phrases

Helge Ewers Seminar

IELTS PrepTOEFL PrepUniversity Students
How forensic scientists fight crime by analyzing handwritingC1
3
49 phrases

How forensic scientists fight crime by analyzing handwriting

IELTS PrepTOEFL PrepUniversity Students
How are vaccines made? What are vaccine adjuvants immune stimulators? #myelomaC1
2
59 phrases

How are vaccines made? What are vaccine adjuvants immune stimulators? #myeloma

IELTS PrepTOEFL PrepUniversity Students
Antimycobacterials | Anti-TB DrugsC1
1
530 phrases

Antimycobacterials | Anti-TB Drugs

IELTS PrepTOEFL PrepUniversity Students
Dr. Isabelle Ray-Coquard | What Has Changed in Clinical Practice for ovarian Cancer in 2025?C1
1
80 phrases

Dr. Isabelle Ray-Coquard | What Has Changed in Clinical Practice for ovarian Cancer in 2025?

IELTS PrepTOEFL PrepUniversity Students
【Veterinary Sciences】Porcine Reproductive and Respiratory Syndrome Virus GZ2022 StrainC1
1
40 phrases

【Veterinary Sciences】Porcine Reproductive and Respiratory Syndrome Virus GZ2022 Strain

IELTS PrepTOEFL PrepUniversity Students
Your genes affect your education. Here’s why that’s controversial. | Kathryn Paige HardenC1
4
55 phrases

Your genes affect your education. Here’s why that’s controversial. | Kathryn Paige Harden

IELTS PrepTOEFL PrepUniversity Students

Vocabulaire et conseils d’expression pour cette leçon

Cette vidéo contient 27 phrases et 373 mots à répéter en shadowing. La partie parlée dure 2:30. Le locuteur parle à un rythme régulier d’environ 149 mots par minute, confortable pour le shadowing. Seuls 66 % des mots font partie des 3 000 mots les plus courants en anglais, le vocabulaire est donc exigeant.

Vocabulaire clé de cette vidéo

15 mots de la vidéo à retenir, avec leur prononciation et leur sens :

MotPrononciationSens
mutant nom/ˈmju(t)n̩(t)/mutant
strand nom/ˈstɹænd/brin, toron
mutation nom/mjuˈteɪʃən/mutation
sequence nom/ˈsiː.kwəns/suite, séquence
curve nom/kɚv/courbe
detection nom/dɪˈtɛk.ʃən/détection
melt verbe/mɛlt/fondre, se dissoudre
sensitive adjectif/ˈsɛn.sɪt.ɪv/sensible
obtain verbe/əbˈteɪn/obtenir, se procurer
variation nom/ˌvɛəɹiˈeɪʃn̩/variation
detect verbe/dɪˈtɛkt/déceler, détecter
axis nom/ˈæksɪs/axe
assist verbe/əˈsɪst/assister, aider
hence adverbe/ˈhɛns/d'ici
rapid adjectif/ˈɹæp.ɪd/rapide

Prononciation à surveiller

  • Les sons « sh » et « zh »: mutation /mjuˈteɪʃən/, detection /dɪˈtɛk.ʃən/, variation /ˌvɛəɹiˈeɪʃn̩/, identification /aɪˌdɛn(t)ɪfɪˈkeɪʃn̩/, dissociate /dɪˈsoʊ.ʃi.eɪt/
  • Mots longs — placez bien l’accent: identification /aɪˌdɛn(t)ɪfɪˈkeɪʃn̩/, simultaneously /ˌsaɪmlˈteɪnɪəsli/, homozygous /ˌhəʊməʊˈzaɪɡəs/, dissociate /dɪˈsoʊ.ʃi.eɪt/, dissociation /dɪˌsoʊsiˈeɪʃən/

Comment s’entraîner avec cette vidéo

  1. Écoutez la vidéo en entier une fois sans parler et notez les mots que vous ne connaissez pas.
  2. Répétez phrase par phrase à vitesse normale, en reprenant chacune jusqu’à ce que votre rythme corresponde à celui du locuteur.
  3. Enregistrez-vous et comparez avec l’original, en faisant attention à des mots comme mutant, strand, mutation.

Qu'est-ce que la technique du Shadowing ?

Le Shadowing est une technique d'apprentissage des langues fondée sur la science, développée à l'origine pour la formation des interprètes professionnels. Le principe est simple mais puissant : vous écoutez de l'anglais natif et le répétez immédiatement à voix haute — comme une ombre suivant le locuteur avec un décalage de 1 à 2 secondes. Les recherches montrent une amélioration significative de la précision de la prononciation, de l'intonation, du rythme, des liaisons, de la compréhension orale et de la fluidité.

Technique du shadowing : lire le guide complet étape par étape →