With markets turning more volatile and tech growth stories turning sour, beaten down biotech stocks are getting another look.

That's why, for the "Off the Charts" segment of Tuesday's Mad Money episode,  Jim Cramer checked in with colleague Carolyn Boroden, who runs the FibonnacciQueen.com website and also contributes to RealMoney.com.

While it may still be early too jump on stocks in the sector, Boroden told Cramer that there are several names worth watching for buying opportunities once some key technical changes appear in their charts.

Cramer and Boroden started by looking at a daily chart of the iShares NASDAQ Biotechnology ETF (IBB) . Boroden pointed out that IBB found support during February's selloffs from symmetry, the tendency for stock swings to terminate at levels similar or equal to past swings. For the IBB, the peak-to-trough decline was $18.28, which was almost the same as the previous big decline of $18.36 going into the lows in November of 2016.

By analyzing the size of the IBB's past swings, Boroden was able to identify an area of possible support for the ETF. After the IBB came down 18 dollars, Boroden watched for confirmation of a bottom. When those buy triggers started to appear in mid-February, she knew that buying the IBB was a decent bet.

So as long as the biotech ETF holds above its Feb. 9 low of $101, down about $9 from where it is now, Boroden believes it can continue to power higher, heading to its next ceiling of resistance at $124 and perhaps even going all the way to $130. Boroden expects the IBB to retest its March 2 low, and that's where she'll be waiting for the next buy signal.

Boroden is watching two biotech stocks: Regeneron (REGN) and Celgene (CELG) .

She and Cramer first looked at a daily chart of Regeneron, a company behind Eylea, a treatment for macular degeneration. After surging above $500 last summer, Regernon's spent month after month getting pummeled down to $333, as of now. But Boroden thinks we could soon get a tradable low in this stock.

Boroden's methodology depends on a series of ratios discovered by the medieval mathematician Leonardo Fibonnaci. She takes past swings in a stock and runs them through the prism of these Fibonacci ratios to spot areas where that stock is likely to change its trajectory. One of most important ratios is the 127.2% extension -- where moves up or down tend to terminate. Regeneron is approaching a 1.272% extension of its run from April of last year into June; meaning it has erased that gain and will have gone 27.2% further if the stock hits $310. No surprise then that Regeneron bottomed at $313 in mid-February.

Boroden also uses this method to analyze the X-axis of the chart, time. She measures the duration of past swings, runs them through the same Fibonacci prism, and finds dates where a stock is likely to change course. Regeneron got a bunch of these Fibonacci time cycles in mid-February, which is exactly where it started rebounding. In the case of symmetry, Regeneron started declining in late January. Boroden measured the two previous swings -- they lasted for $84 and $82. In February Regeneron stopped going down after an $82 decline.

In the next version of Regeneron's daily chart, the stock has been trading steadily sinking, making a consistent pattern of lower lows and lower highs. Boroden says that pattern remains intact. The stock rallied $39 from the February lows to its peak yesterday, before getting banged down along with the rest of the market. That matters to Boroden because Regeneron's prior rallies have tended to last for $33 to $50.

If Regeneron is going to get its groove back, it needs to break out of this pattern, which means clearing a bunch of hurdles in the $350s and mid $360s. That may seem far away after yesterday's beating, but it's what Boroden's watching for long-term to judge whether Regeneron can snap out of its bearish funk. If it can break out into the mid-$360s, Boroden could see the stock going to $455, but that's a mighty big if.

Celgene is another stock that has been obliterated since last fall, coming down from $147 to $87. The daily chart has been brutal. But Boroden thinks the stock has found a floor of support in the mid $80s, down a point or two from where it's currently trading. If Celgene can break out into the mid $90s from here, that would tell Boroden that the stock is ready to run. Of course, it tested those levels last week and failed to clear them, but she's patiently waiting for the stock to make another attempt. Until then, she recommends staying on the sidelines.

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