I Am Diagnosed as a Medical Titan

Chapter 176: Chapter 134: Sequencing Before Dawn (Part 3)

”Measure the concentration,” Jiang He said, handing the sample to Lu Xiaolin.

Lu Xiaolin took the sample to the NanoDrop spectrophotometer. He pipetted one microliter onto the measurement pedestal and lowered the cantilever arm.

A curve immediately appeared on the computer screen.

”Concentration: 120 ng/μl. A260/280 ratio: 2.02,” Lu Xiaolin reported quickly. ”The extraction is absolutely perfect! Extremely high purity, with no protein or phenol contamination!”

Chen Hao and the others let out a long sigh of relief and glanced at each other.

’We did it!’

Without hesitation, Jiang He ordered, ”Start reverse transcription immediately. RNA degrades easily, so we have to convert it into stable cDNA right away.”

”What primers should we use?” Lu Xiaolin asked.

”Use random hexamers for reverse transcription of the whole transcriptome.”

Jiang He walked to the refrigerator and took out a reverse transcription kit. ”We don’t need specific primers. During the PCR stage, we’ll use the universal primers for the conserved regions of Influenza A’s HA (hemagglutinin) and NA (neuraminidase) genes to fish out the target fragments.”

Looking at the reagents in his hand, a flicker of emotion crossed Jiang He’s eyes.

’In truth, if this were a completely new and unknown virus, we wouldn’t have even scratched the surface in these few hours tonight.’

’Just designing the primers would stump the top labs in all of China for two weeks.’

’But he was different.’

’He remembered the genetic map of H1N1, knew the weaknesses of its outer membrane proteins, and even which primers would most easily amplify it.’

’It was essentially the equivalent of having the answer key and working backward to deduce the steps to the solution.’

’That was why he could be so efficient.’

The reverse transcription reaction mix was prepared.

It was placed into the PCR machine.

Incubate at 42℃ for 60 minutes, then heat to 70℃ for 5 minutes to inactivate the reverse transcriptase.

「5:30 AM」

Reverse transcription was complete.

The extremely fragile RNA had finally been converted into relatively stable DNA.

”Prepare for the PCR amplification.”

”We need to separately amplify its HA, NA, M, and PB1 gene fragments.”

Jiang He and the team skillfully finished loading the samples into the PCR plate.

They placed it into the real-time quantitative PCR instrument.

The thermocycler was programmed: pre-denaturation at 95℃ for 5 minutes, followed by 40 cycles of denaturation at 95℃ for 15 seconds and annealing/extension at 60℃ for 1 minute.

”It’ll take about an hour and a half.”

Jiang He peeled off his outer layer of latex gloves and glanced at the wall clock.

The six students in the lab were already exhausted.

Jiang He walked into the hallway, found the number for Minister Lin’s secretary, and dialed.

The phone rang seven or eight times before connecting.

”Secretary Wang, this is Jiang He. I’m sorry to disturb you at this hour.”

”Mm... It’s all right. What is it?”

”Secretary Wang, I need you to report something to Minister Lin immediately. Affiliated Hospital No. 1 has admitted a businessman from Mexico, and he’s been confirmed to have an extremely high-risk case of severe pneumonia from an unknown cause. Furthermore, last night, the Provincial People’s Hospital and City Eighth Hospital each admitted a severely ill patient who had confirmed close contact and environmental exposure to him. My assessment is that this is a textbook case of a virulent respiratory disease with an extremely high rate of human-to-human transmission.”

Lying in bed, Secretary Wang shot upright, breaking out in a cold sweat from the shock.

”Are you sure? Has the local CDC reported anything?”

”The CDC’s procedures are too slow. I’m currently in Professor Sun Changming’s lab at Affiliated Hospital No. 1 running the gene sequencing. I need the provincial department to use its administrative power immediately to find a taxi. The driver’s surname is Lin. He drove the Mexican businessman three days ago and is currently out of contact. It’s highly likely he has already fallen ill. If he continues moving around the city, the consequences will be unimaginable.”

”Jiang He, do you have conclusive laboratory evidence right now?”

”The evidence is almost ready. But that driver... for every extra minute he’s out there, he could infect ten more people. Secretary Wang, lives are at stake.”

There were a few seconds of silence on the other end of the line.

”I understand. I’ll report to Minister Lin immediately. The moment you have lab results, notify me!”

Jiang He looked at his phone and let out a small sigh of relief.

’Thank goodness I have the minister’s contact information!’

「7:15 AM」

The PCR amplification was finished.

”Run an agarose gel electrophoresis to see if we have bands!” Lu Xiaolin immediately took out the PCR product.

Fifteen minutes later, the electrophoresis results appeared under the UV gel imager.

On the screen, at the position corresponding to the amplified fragment size, an extremely bright, specific band had appeared.

No primer dimers, no non-specific amplification.

”Beautiful!” Chen Hao couldn’t help but pump his fist.

Jiang He ordered, ”Prepare the sequencing reaction. Recover the PCR product with a purification column, add the BigDye sequencing reagent, and run the sequencing PCR.”

Another round of delicate work began.

「10:00 AM」

Sunlight now fully illuminated the skies of Yangcheng.

In Sun Changming’s lab, everyone was gathered around the computer screen of the ABI 3130xl Genetic Analyzer.

The capillary electrophoresis for the sequencing was performing its final signal read.

On the screen, differently colored fluorescent peaks began to appear one by one.

Red, green, blue, and black, representing the four bases A, T, C, and G, respectively.

”We have peaks. The baseline is flat, and the peaks are extremely sharp. The sequencing quality is very high,” Cheng Xiyao said, staring intently at the screen without blinking.

As the sequencer ran, a long string of base sequences was read out, generating a text file in FASTA format.

”Export the sequence data. Chen Hao, open the BLAST alignment software.”

Chen Hao immediately imported the sequence files for the three gene fragments—HA, NA, and M—into the locally built influenza virus database to perform a similarity comparison.

The progress bar filled in an instant.

The alignment results popped up.

Chen Hao stared at the English text and data on the screen, stunned.

”Old Jiang... This... this can’t be right. Is the database broken?”

”What is it?”

”Its HA gene fragment... the closest match is... the classical swine flu virus from North America? And its NA and M fragments match the Eurasian avian-like swine flu virus? Then... how is its PB1 gene highly homologous with the human seasonal H3N2 influenza virus?”

Lu Xiaolin shook his head. ”That’s impossible. A swine virus, an avian virus, and a human virus... how can they all be pieced together in the same viral strain? We must have made a mistake.”

Everyone was crestfallen.

Only Jiang He let out a long, slow breath.

’This is it.’

And why was this the result?

The reason was simple.

When a pig is simultaneously infected with avian, human, and swine flu viruses, its respiratory epithelial cells act as a natural mixing vessel. The different viruses undergo genetic reassortment there, ultimately giving birth to this brand-new variant that combines traits from all three and poses a fatal threat to humanity—

The Influenza A H1N1 virus.

Jiang He said softly, ”The database isn’t broken. This is an unprecedented, quadruple-reassortant novel influenza virus. The human immune system is completely unprepared for it.”

The lab fell deathly silent.

The six students stared blankly at the screen.

’Did Jiang He mean... that they had just personally discovered a new virus?’

Just then, Jiang He’s phone began to vibrate.

The caller ID read: Zheng Liyan.

Jiang He answered the phone.

”Jiang He, morning.”

”Academician Zheng, good morning.”

After briefly explaining the situation from start to finish, Jiang He said:

”...I just finished the sequencing, and the results are in. Gene fragments from the North American classical swine flu, Eurasian swine flu, and human flu have reassorted within this virus. It’s a new, quadruple-reassortant variant strain. A conventional rapid antigen test would only show a positive for Influenza A, perfectly concealing its true identity.”

Zheng Liyan on the other end of the line went silent.

The great Spanish Flu of 1918, the Asian Flu of 1957, the Hong Kong Flu of 1968...

All of them were caused by antigenic shifts resulting from genetic reassortment!

And every time, they claimed tens of thousands of lives.

Zheng Liyan asked, ”Are you certain the sequencing results are correct?”

Jiang He replied, ”I’ll email you the FASTA sequence file and the BLAST comparison results immediately.”

”Good. If the data is confirmed, I will personally report it to the Ministry of Health.”

The briefing was over.

Jiang He put down his phone and turned to the six students behind him.

They had been up all night, but none of them felt the least bit sleepy.

Because they all realized they were part of a plan to save an entire city...

This wasn’t as simple as saving one or two people.

”Chen Hao, print out the sequencing report. Let’s go.”

”Where are we going?”

”The Medical Affairs Department.”