Noisy sequence refers to unwanted signals or errors that occur during the sequencing process. These can cause the data to be wrongly interpreted. Main causes of noisy sequence include: 

• Low DNA concentration, which results in low signal intensity necessitating the artificial amplification of background noise by the software
• Low quality DNA
• Multiple primer sites
• Inefficient primer annealing
• Inadequate primers
• Noisy data caused due to arbitrary priming of a N-1 primer synthesis