Skip to main content
Premium Trial:

Request an Annual Quote

'Unappreciated Variations'

What differentiates people from each other, genomically speaking? Is it our SNPs, our CNVs, our rearrangements? A new study published in Nature Biotechnology suggests that it's really "unappreciated variations in [the genome's] fundamental architecture," rather than single point-by-point mutations that really make up the differences between people, reports Wired's Brandon Keim. While SNPs are the most common variations and the most widely studied for their associations with disease, large-scale changes like duplications and reversals, or additions or omissions of long DNA sequences, are less studied, Keim says. The study's authors say that these longer sequences are more specific to individual people than SNPs are, and suggest that traditional genome sequencing techniques are too focused on short reads to show the whole picture. "It might seem counterintuitive that big changes have been harder to detect than small ones, but it’s a consequence of how genomes are read," Keim says. "Every method involves breaking long DNA sequences — the human genome contains three billion DNA pairs — into pieces, then trying to reassemble them. The methods vary according to fragment size and reassembly technique, but as a rule it’s far less expensive and time-intensive to use small fragments." But like a jigsaw puzzle, it would be easier to put the picture together if we were using larger pieces, he adds.

The Scan

Pig Organ Transplants Considered

The Wall Street Journal reports that the US Food and Drug Administration may soon allow clinical trials that involve transplanting pig organs into humans.

'Poo-Bank' Proposal

Harvard Medical School researchers suggest people should bank stool samples when they are young to transplant when they later develop age-related diseases.

Spurred to Develop Again

New Scientist reports that researchers may have uncovered why about 60 percent of in vitro fertilization embryos stop developing.

Science Papers Examine Breast Milk Cell Populations, Cerebral Cortex Cellular Diversity, Micronesia Population History

In Science this week: unique cell populations found within breast milk, 100 transcriptionally distinct cell populations uncovered in the cerebral cortex, and more.