Chapter 758 Our approach
The technology for making DNA for dogs is slightly later than that for humans.
The main thing is to solve the problem of genetic markers. We need to determine which genetic markers are stable and can be used for comparison and testing. The physical evidence identification center of the ministry specializes in this. Around the beginning of 2000, it first completed the DNA identification of cows, mainly for "why do you say this cow belongs to you?"
The ancient method of marking cattle and horses is still not sure by doing a paternity test for cattle, especially if the other party intends to take your cattle away, or even steal it, whether there is still a mark on the buttocks is a matter of debate.
As for DNA testing of dogs, the more famous case is a case in Estonia. A young woman was bitten to death by a dog in a village. The forensic doctor used the dog hair and saliva spots collected from the woman's coat to conduct DNA tests on 6 dogs belonging to several nearby households. After inspection and comparison, the suspect dog was finally identified.
In modern times, dog DNA identification has become very simple and easy, and the development direction of this technology has shifted to rapid DNA screening. The main ones are rapid test kits, used by departments such as market supervision, which can usually quickly detect the genes of dogs, foxes, minks, cats, ducks, rats, etc.
That is to say, you can wipe a piece of meat product of unknown identity and insert it into the box. In a few minutes, you can know whether it contains dog, fox, mink, cat, duck, rat, etc. .
The so-called selling of dog meat with sheep's heads has been around since ancient times. In modern times... there have been horse meat incidents in 16 countries in Europe, where horse meat was used to pass off as beef. The type of DNA testing kit illustrates another less interesting phenomenon. That is to say, the meat on the market has reason to be suspected of being adulterated, and the source of adulteration may not necessarily be dog or duck meat, but cat meat, fox meat, mink meat...
In addition, raccoons belong to the canidae family and are often used to pass themselves off as dog meat.
All in all, most of the cases that the Evidence Identification Center performs DNA on dogs are economic cases, so suddenly there is a murder case involved, or a serious case, and the technicians who handle it are actually quite excited.
Before Jiang Yuan could complete the autopsy, the technician from the Physical Evidence Identification Center brought the report to his door all the way.
"Well, the body of the dog you want to identify is a horse dog." The technician asked for directions and looked very happy when he saw Jiang Yuan and others.
"Ah... Captain Lou is here. Could you please bring it here in person?" Zhan Gong was performing skull restoration surgery and was dizzy. He came with the skeleton in his arms to greet him and introduced it to Jiang Yuan.
"We are so acquainted, so we won't shake hands anymore...Hello, Medical Examiner Jiang, I am Lou Fengguo..." Lou Fengguo ran up and stared at Jiang Yuan, like a fan who bought the front row at a concert.
The report he held in his hand also looked like the tickets bought by the fans in the front row. Jiang Yuan thanked him repeatedly and took it over to look at.
Lou Fengguo introduced from the side: "The Malinois is a Belgian shepherd dog, and it is also a common working dog. However, this kind of dog is also one of the dogs that gets into most troubles. It is particularly easy to get excited. When working, the working hours are long, but it is used as a pet. In fact, it is very easy to get into trouble. Especially the cross between a horse and a dog. The character of a horse and dog is already very unstable, and it becomes even more unstable after a cross."
Jiang Yuan nodded and asked, "Where's this one?"
"Pure." Lou Fengguo clicked on the watch in the report with his hand, and then said: "The price of horse dogs is not expensive. Of course, there may be particularly expensive ones, but the average purebred horse dog is only one or two thousand, two or three. It depends on where you bought it from. It’s troublesome to raise this dog in the city. It eats a lot, poops a lot, takes a long time to walk, and it also tends to shed.”
"But if it is used as a police dog or for work, it is very suitable, right?" Zhan Kong didn't want to look at the skull anymore and sat down to talk.
Lou Fengguo nodded: "That's for sure. Horse dogs are very capable of working. They can climb trees, climb over walls, and have super bounce. Police horse dogs can easily go up to the second floor. They are also very vigilant and can bite hard. . In addition, if you keep it as a pet, it will be excited for a long time, and being easily excited is a disadvantage. As a working dog, it is perfect."
"Can we find its owner or related personnel through DNA?" Jiang Yuan naturally went to solve the case by taking its DNA.
Lou Fengguo became excited at this time, and the short hairs on his arms stood up. He said so much, but what he was waiting for was Jiang Yuan's words.
"If it were someone else, I would probably have to wait for you to get the DNA and compare it. The pedigree of horses and dogs is still very complicated." Lou Fengguo said with a proud smile: "But I still have some experience in this aspect."
"Hmm... do you want to join our task force?" Jiang Yuan's words were exactly what Lou Fengguo wanted, but they directly surprised Lou Fengguo.
Lou Fengguo couldn't help but touch his short hair: "You don't even ask me about the technology I plan to use?"
"I don't know much about DNA testing." Jiang Yuan replied. Then he thought that the other party was not just a perfunctory leader, so he added: "What technology are you going to use?"
"Dogs of different bloodlines must have some stable DNA inheritance. The origins of our domestic dogs are relatively simple. It just so happens that I have some knowledge in this aspect. Well, to be honest, people in the circle tell me that I understand Here comes the Dog Emperor." Lou Fengguo became proud as he spoke.
Probably a bit proud indeed.
With the number of outstanding people in the capital, since Lou Fengguo dares to claim the title of emperor, he must be at least LV3 or above. If it were not a circle of pure enthusiasts, Dong Du of Lou Fengguo might still be able to rise.
Jiang Yuan couldn't help but think of the first skill he acquired, the LV5 dog rice skill, which came from the legacy of the victim Chen Manli. Chen Manli has not received any professional training. It is just pure hobby and talent. She is completely self-taught and has reached the level of LV5.
Jiang Yuan estimated that if he entered the DNA laboratory, his DNA identification level would be at least 8, and he might only have a 4 level.
This thing is so-called easy to learn but difficult to master. The simplest operation is similar to self-testing nucleic acid. But if you get a little more advanced, the difficulty is theoretical. For example, you must pay attention to the equipment used and which country and company produced it. , otherwise the results will be different.
The processing of test samples is even more exquisite, including the aqueous solution to soak in, the homogenization treatment plan, temperature, enzymes, and the types of solutions that are added multiple times, especially the primers. The complexity is not exaggerated to LV5.
Although the DNA identification of different organisms is similar, as Lou Fengguo said, it is extremely difficult to trace the origin of dogs and determine some of their stable inheritance.
"Then I'll leave the task of finding the dog to you." Jiang Yuan made a decision quickly.
Lou Fengguo was a little uncomfortable with it, and couldn't help asking: "Don't you want to inspect it?"
Jiang Yuan glanced at him and began to put on his gloves again. While preparing to continue the dissection, he asked: "Do you really understand dogs? Can you trace the lineage and origin of this dog through the existing skeletons?"
Lou Fengguo immediately said: "It's no problem to trace the bloodline. If you can trace the origin, you may need a little luck..."
"That's enough." Jiang Yuan interrupted Lou Fengguo.
Lou Fengguo: "Is this enough?"
"Well, we are concerned about this case from top to bottom. I am from Ningtai, and I have no power to manage you..."
"How could it be possible? With your current reputation, Captain Jiang..."
Jiang Yuan waved his hand: "What I mean is that this case is very expensive and involves a lot. Not only the Zhengguang Bureau, but also everyone from top to bottom is paying attention. I don't need to manage them one by one, and I don't have time..."
"Captain Jiang, don't just say scary things." Zhan Gong quickly stopped Jiang Yuan and said, "I feel a little cold."
Jiang Yuan said "Oh" and changed his tone to a gentler tone and said: "Captain Lou, you are welcome to join the task force. Just try to make things as good as possible. Tao Zhi and the others are watching everything you do."
…
Not only was Tao Lu watching, Qi Changye and his colleagues were becoming increasingly anxious.
After 24 hours of personal efforts, Qi Changye couldn't wait to arrive at the anatomy center.
The large letters of the anatomy center mounted on the wall are dusty. From a distance, it looks like an ordinary building, but in the capital, nothing is ordinary.
The corpses must be gathered together for a table and a half of mahjong to create a scale and attract attention.
Before Qi Changye entered the door, he also scratched his hair, making it look messy and covering his thinking head.
"Captain Jiang..." Qi Changye entered with a shrill voice.
When Jiang Yuan heard the scream, he first took a serious look at the skeleton on the dissection table to make sure it was not the scream, then turned to look at Qi Changye and said: "Qi Chu, I haven't finished the dissection here yet... Are there any bodies again?”
"I don't dare, alas... I don't know either." Qi Changye sighed, and then said: "We were interrogating all day yesterday and encountered some problems."
"what is the problem?"
"No one really knows what happened to these corpses." Qi Changye said a little solemnly and a little puzzled: "I saw them coming this way with my own eyes that day."
Jiang Yuan frowned slightly when he heard this. Indeed, from Qi Changye's point of view, there is a high probability that the body was left behind by the previous spy case. Ordinarily, there must be some rumors...
"The murderer ran away?" Jiang Yuan gave a guess.
"They all ran away? It's unlikely." Qi Changye also agreed with Liu Jinghui's speculation. This method of burying corpses requires several people to work together.
Moreover, as far as Qi Changye feels, if four or five people are required to form a team to bury the body, then the team cannot only have four or five people, because something may happen among everyone, and someone may be injured and ask for leave. If there is a shortage of people, either Others carry it all, or they have to be supplemented.
Supplementation is the most likely scenario, so there should be quite a few insiders.
Furthermore, in the sequence of espionage cases, the level of these insiders is probably not high. It is normal within the agency to act below the intelligence level. Therefore, when many people were arrested, all the insiders ran away. It's also unreasonable.
Qi Changye was silent for a moment, and then asked in a low voice: "Have you found my special love?"
"There is nothing that matches the current situation." Jiang Yuan spread his hands and thought about it before saying, "However, it is impossible to find all the corpses buried underneath."
"This...sigh..." Qi Changye sighed.
Seeing this, Jiang Yuan coughed twice and said, "If things don't go well here, why don't you try our method?"