The Heilbronn DNA Mixup

I wish I’d written earlier about this to appear really smart. Anyway, here’s the backstory: DNA traces of an unknown eastern-European woman had been found at almost

The Culprit

17 crime scenes, including two murders (including a 22 year old police officer) but also car jackings, unprofessional break-ins and on a bullet fired in a marital dispute. The crimes where spread around a large area including south-west Germany, France and Switzerland.

It now turns out that the several-hundred-men task force might have really been chasing a phantom. Alarmed by the apparent randomness of the crimes, involving both highly professional work and seemingly amateur break-ins, they started checking for contaminations in the labwork. The likeliest suspect now are the cotton swabs used to collect evidence at the crime scene. All the swabs used in the forensics works were sourced from the same supplier, a company in northern Germany that employs several eastern-European women that would fit the profile. Even more inciminating, the state of Bavaria lies right in the center of the crimes’ locations, without ever finding matching DNA in crimes on its territory. Guess what: they get their cotton swabs from a different supplier.

While the suspicion had already been growing in the last few months, the smoking gun apparently was a case where they tried to match a burned (male) corpse to DNA collected from fingerprint samples an asylum-seeker had given a few months earlier. The first test showed a match between those fingerprints and the Phantom’s DNA while a second test did not.

By the way: contaminated cotton swabs aren”t as trivial to avoid as one might think. It’s relatively easy to sterilize cotton to prevent infections. Forensics however require a complete destruction or removal of any DNA contamination, which is apparently a lot harder.

Shooting mosquitos with lasers

Ever since I read a job posting regarding tracking bees with a radar I have dreamt about combining a system like that with a laser to automatically (or manually for extra fun) shoot mosquitos. It seems I’ve not been the first nor the last person to have that idea. While I quickly learnt that the bees in that project were equipped with radar-reflecting material, I found an old post at some brainstorming website that discussed a system using three microphones to triangulate a mosquito’s position. Now a similar idea has made the Wall Street Journal’s frontpage. Wood and Kare are testing system that currently uses image recognition to locate the bugs. Using radar is also discussed in that article, so it seems that radar actually has at least the theoretical ability to track a single mosquito. Must be fun to get paid to work on a project like that.

More on pyMOL

The people from pyMOL responded to my last post, where I made a comment that DeLano is “heavily trying to commercialize” pyMOL. I felt I should write a little more on that.

Firstly, I wasn’t really passing judgement. There’s nothing wrong with commercial software, I’ve written enough of that myself. Nor is there anything wrong with soliciting contributions to open source software projects, especially when they’re as good as pyMOL. However, looking at the pyMOL website and download page, it seems that DeLano Sc. is trying to create the impression that a subscription is necessary. There’s a list of commercially available builds and bunch of ways to get inferior or education-only versions. The source download is right there at the bottom, but I somehow missed that when I first went to the site and I know of at least two other people who where also confused. All the options are obvious now, but it is a bit misleading for a first-time user.

I guess it’s the old problem of how to get people to contribute to open source project, and the approach is much like MySQL’s. I’m not sure how useful it is, though. A student using pyMOL once or twice for assignments is not going to pay for it anyway. Any researcher or institution, OTOH, will learn quickly that there’s a OSS version available. They’re used to open source, so there shouldn’t be much corporate red tape that can be avoided with buying commercially, nor will they afraid of compiling it themselves or require much support. The actual value of a subscription is therefore quite low, and many will just choose to pay to support the project.

There is, then, not much use in misleading people into thinking the OSS version is inferior, or hiding it below a long list of commercial options. There’s nothing wrong with asking people for a little goodwill, and many will happily do so especially when it’s not their own budget. I just wished DeLano where a bit more open about it.

Update: the response by pyMOL below is worth reading.