Why divide the lane in sequencing?

[Hyunmin]

Is there the important reason when sequencing the genome in some lane?

For example, BGI sequencing data has raw data with some lane.

I guess, it can decrease the risk of failed sequencing in one lane at once.
(de novo, whole genome data..)

Any other reason? (like experiment, analysis..or?)

Thanks.

[dpryan]

Do you mean (1) multiplexing samples on a single lane, (2) running a sample across multiple lanes, or (3) a combination of the two?

(1) Mostly useful for small genomes or things like RNAseq or exome sequencing.
(2) Nice if you need more reads, such as sequencing larger genomes.
(3) As you suggested, this decreases risks from lane failures or other odd lane-effects.

[Hyunmin]

I mean,

(2) running a sample across multiple lanes

If we can sequence 'A' genome with 2 lane, the output(rawdata) has 2 lane.

*this data size is for example.

T1211D1108_ACTTGA_L001_R1_001.flt.fastq.gz (20MB)
T1211D1108_ACTTGA_L001_R2_001.flt.fastq.gz (20MB)
...
T1211D1108_ACTTGA_L002_R1_001.flt.fastq.gz (20MB)
T1211D1108_ACTTGA_L002_R2_001.flt.fastq.gz (20MB)
...

but, (like BGI) the sequencing provider give raw data in below.

T1211D1108_ACTTGA_L001_R1_001.flt.fastq.gz (10MB)
T1211D1108_ACTTGA_L001_R2_001.flt.fastq.gz (10MB)
...
T1211D1108_ACTTGA_L002_R1_001.flt.fastq.gz (10MB)
T1211D1108_ACTTGA_L002_R2_001.flt.fastq.gz (10MB)
..
T1211D1108_ACTTGA_L003_R1_001.flt.fastq.gz (10MB)
T1211D1108_ACTTGA_L003_R2_001.flt.fastq.gz (10MB)
..
T1211D1108_ACTTGA_L004_R1_001.flt.fastq.gz (10MB)
T1211D1108_ACTTGA_L004_R2_001.flt.fastq.gz (10MB)
..

[dpryan]

That actually looks more like (3), where the samples are multiplexed with something else and run across multiple lanes. It's mostly a hedge against a lane failing or having other odd issues.