cDNA

Complementary DNA (cDNA) is a DNA molecule synthesized from a single-stranded RNA (typically messenger RNA, or mRNA) template through the action of the enzyme reverse transcriptase. This process yields a DNA copy that is complementary to the original RNA sequence. Because cDNA is derived from mature mRNA, it lacks intronic sequences found in genomic DNA and includes only exonic (protein-coding) regions. This makes cDNA particularly valuable for molecular biology applications requiring the study of expressed genes, as it represents a direct genetic “snapshot” of a cell’s transcriptome at a given time.

Content and Synthesis

The content of cDNA consists exclusively of sequences that were present in the original mRNA molecules. It typically includes the 5' and 3' untranslated regions (UTRs) and the open reading frame (ORF) that codes for proteins. The synthesis of cDNA involves several technical steps:

  • RNA Isolation: High-quality mRNA is isolated from cells or tissues.
  • Primer Binding: Oligo(dT) primers (which anneal to the poly-A tail of mRNA) or random hexamers bind to the mRNA.
  • Reverse Transcription: Using reverse transcriptase, the enzyme extends from the primer, synthesizing a complementary strand of DNA from the RNA template.

Applications of cDNA

cDNA finds extensive application in molecular biology and biotechnology:

  • Gene Cloning and Expression: Because it contains only coding regions, cDNA is ideal for cloning eukaryotic genes into expression vectors for protein production, bypassing intron removal that is required when using genomic DNA in prokaryotic systems.
  • cDNA Libraries: Collections of cDNA sequences can be stored in libraries, representing the set of genes expressed in a particular cell type or under specific conditions. These libraries are essential resources for gene discovery, comparative genomics, and screening for gene function.
  • Quantitative PCR (qPCR) and RT-PCR: cDNA serves as the template for quantitative measurement of gene expression. Reverse transcription polymerase chain reaction (RT-PCR) amplifies specific cDNA segments to quantify mRNA levels, aiding in diagnostics, gene expression profiling, and validation of gene expression differences under various experimental conditions.

By focusing on the expressed regions of the genome, cDNA techniques allow researchers to analyze protein-coding potential and expression dynamics without the confounding presence of non-coding intronic sequences, facilitating a variety of technical applications in genomics, transcriptomics, and biotechnology.

AffiDNA®​ cfPure DNA Free Plasma
CAT# AFG-BCH-1411
Size: 50 mL
715.23 715.23 USD
AffiDNA®​ DNA Free Plasma
CAT# AFG-BCH-1410
Size: 5 mL
421.98 421.98 USD
733.60 733.6 USD
733.60 733.6 USD
AffiDNA®​ Optimax First Strand cDNA Synthesis Kit
CAT# AFG-BCH-1111
Size: 100 Reactions
874.30 874.3000000000001 USD
AffiDNA®​ cDNA - Human Tumor Cell Line: Raji
CAT# AFG-BCH-1110
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Human Tumor Cell Line: MCF 7
CAT# AFG-BCH-1109
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Human Tumor Cell Line: K 562
CAT# AFG-BCH-1108
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Human Tumor Cell Line: Jurkat
CAT# AFG-BCH-1107
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Human Tumor Cell Line: Hela
CAT# AFG-BCH-1106
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Human Tumor Cell Line: A431
CAT# AFG-BCH-1105
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Testis
CAT# AFG-BCH-1104
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Stomach
CAT# AFG-BCH-1103
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Spleen
CAT# AFG-BCH-1102
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Small Intestine
CAT# AFG-BCH-1101
Size: 40 Reactions
1,052.80 1052.8 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Rectum
CAT# AFG-BCH-1100
Size: 40 Reactions
1,052.80 1052.8 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Placenta
CAT# AFG-BCH-1099
Size: 40 Reactions
1,052.80 1052.8 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Skeletal Muscle
CAT# AFG-BCH-1098
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Lung
CAT# AFG-BCH-1097
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Liver
CAT# AFG-BCH-1096
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Kidney
CAT# AFG-BCH-1095
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Heart
CAT# AFG-BCH-1094
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Colon
CAT# AFG-BCH-1093
Size: 40 Reactions
1,052.80 1052.8 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Brain
CAT# AFG-BCH-1092
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Bladder
CAT# AFG-BCH-1091
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Rat Normal Tissue: Adipose
CAT# AFG-BCH-1090
Size: 40 Reactions
1,052.80 1052.8 USD
1,163.05 1163.05 USD
1,163.05 1163.05 USD
1,163.05 1163.05 USD
1,163.05 1163.05 USD
1,163.05 1163.05 USD
1,163.05 1163.05 USD
1,163.05 1163.05 USD
AffiDNA®​ cDNA - Alzheimer's Disease: Brain: Thalamus
CAT# AFG-BCH-1082
Size: 40 Reactions
1,227.10 1227.1000000000001 USD
1,227.10 1227.1000000000001 USD
1,227.10 1227.1000000000001 USD
1,227.10 1227.1000000000001 USD
AffiDNA®​ cDNA - Alzheimer's Disease: Brain: Pons
CAT# AFG-BCH-1078
Size: 40 Reactions
1,227.10 1227.1000000000001 USD
1,227.10 1227.1000000000001 USD
1,227.10 1227.1000000000001 USD
1,408.75 1408.75 USD
1,408.75 1408.75 USD
AffiDNA®​ cDNA - Depression: Brain: Hippocampus
CAT# AFG-BCH-1073
Size: 40 Reactions
1,408.75 1408.75 USD
AffiDNA®​ cDNA - Dementia: Brain: Hippocampus
CAT# AFG-BCH-1072
Size: 40 Reactions
1,408.75 1408.75 USD
1,408.75 1408.75 USD
1,227.10 1227.1000000000001 USD
AffiDNA®​ cDNA - Alzheimer's Disease: Brain: Cerebellum
CAT# AFG-BCH-1069
Size: 40 Reactions
1,227.10 1227.1000000000001 USD
AffiDNA®​ cDNA - Alzheimer's Disease: Brain: Amygdala
CAT# AFG-BCH-1068
Size: 40 Reactions
1,227.10 1227.1000000000001 USD
AffiDNA®​ cDNA - Parkinson's Disease: Brain
CAT# AFG-BCH-1067
Size: 40 Reactions
1,227.10 1227.1000000000001 USD
AffiDNA®​ cDNA - Multiple Sclerosis Disease: Brain
CAT# AFG-BCH-1066
Size: 40 Reactions
1,227.10 1227.1000000000001 USD
AffiDNA®​ cDNA - Alzheimer's Disease: Brain
CAT# AFG-BCH-1065
Size: 40 Reactions
1,227.10 1227.1000000000001 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Testis
CAT# AFG-BCH-1064
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Stomach
CAT# AFG-BCH-1063
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Spleen
CAT# AFG-BCH-1062
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Small Intestine
CAT# AFG-BCH-1061
Size: 40 Reactions
1,052.80 1052.8 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Rectum
CAT# AFG-BCH-1060
Size: 40 Reactions
1,052.80 1052.8 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Placenta
CAT# AFG-BCH-1059
Size: 40 Reactions
1,052.80 1052.8 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Skeletal Muscle
CAT# AFG-BCH-1058
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Lung
CAT# AFG-BCH-1057
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Liver
CAT# AFG-BCH-1056
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Kidney
CAT# AFG-BCH-1055
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Heart
CAT# AFG-BCH-1054
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Colon
CAT# AFG-BCH-1053
Size: 40 Reactions
1,052.80 1052.8 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Brain
CAT# AFG-BCH-1052
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Bladder
CAT# AFG-BCH-1051
Size: 40 Reactions
830.20 830.2 USD
AffiDNA®​ cDNA - Mouse Normal Tissue: Adipose
CAT# AFG-BCH-1050
Size: 40 Reactions
1,052.80 1052.8 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
890.05 890.0500000000001 USD
890.05 890.0500000000001 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
890.05 890.0500000000001 USD
890.05 890.0500000000001 USD
1,144.15 1144.15 USD
890.05 890.0500000000001 USD
1,144.15 1144.15 USD
1,144.15 1144.15 USD
1,933.75 1933.75 USD
890.05 890.0500000000001 USD
1,761.55 1761.55 USD