Sheldon: I was analyzing our lie and I believe we're in danger of Penny seeing through the ruse.
Leonard: How?
Sheldon: Simple: If she were to log on to SoCal physics group.org forward slash activities forward slash other, scroll down to seminars, download the PDF schedule, and look for the seminar on molecular positronium, well then, bippity boppity boo, our pants are metaphorically on fire!
The Zazzy Substitution - S4-E3
Sheldon: May I point out that for eight long months, I suffered in silence as your female companion filled our apartment with her off key country music caterwauling, the unappetizing spectacle of grinding a pommel stone against her calloused feet in our living room, and night after night of uninformative TV documentaries about the Jersey Shore.
Leonard: Suffered in silence?
Sheldon: Yes, and I would expect you to do the same.
Leonard: Really? SILENCE!?
The Guitarist Amplification - S3-E7
Sheldon Cooper: Leonard, when that woman moved in three years ago, I told you not to talk to her, and now look, we're going to be late for the movies.
The Guitarist Amplification - S3-E7
Penny: Wow, Sheldon. I had no idea you made a board game.
Sheldon Cooper: Oh, Research Lab is more than just a board game. As it says in the box, "the physics is theoretical, but the fun is real."
Leonard Hofstadter: We must not be playing it right.
Sheldon: You have about as much chance of going out with Penny as the Hubble Telescope has of finding that at the center of each black hole there's a little man with a flashlight trying to find the circuit breaker.
The Countdown Reflection - S5-E24
Sheldon: All right, my turn. Howard, Bernadette. DaQH Daj mo...DaQH...
Bernadette: Sheldon! I told you no Klingon.
The Communication Deterioration - S8-E21
Penny: You are a wise man.
Sheldon: Well, Penny, who's smarter, the wise man or the person who comes to him for advice?
Penny: Oh, I guess you're right. Maybe it is the person who asks.
Sheldon: No. It's the wise man. That's why he's called the wise man. You know how I know that? I'm the wise man.
The Vegas Renormalization - S2-E21
Sheldon: While my compatriots are in Las Vegas, I will be enjoying a blissful evening in my personal Fortress of Solitude.
Penny: That's Superman's big ice thingy, right?
Sheldon: You know, I'm in such a good mood, I'm actually finding your tenuous grasp of the English language folksy and charming today.
Penny: Sheldon, have you any idea what time it is?
Sheldon Cooper: Of course I do. My watch is linked to the atomic clock in Boulder, Colorado. It's accurate to one-tenth of a second. But as I'm saying this, it occurs to me that you may have again been asking a rhetorical question.
The White Asparagus Triangulation - S2-E9
Sheldon: Hi Stephanie, I'm sorry I'm late but your companion left me the most undecipherable invitation
Leonard: What invitation?
Sheldon: [From note.] "We're going to the movies" What movie? What theater? What time? If you wanted to make it impossible to find you, you couldn't have done a better job.
Leonard: Oh I could have.
The Panty Piñata Polarization - S2-E7
Sheldon Cooper: Woman, you're playing with forces beyond your ken.
Penny: Your Ken can kiss my Barbie.
Suggested correction: Genes can be dormant. Which allows them to skip generations. Therefor Missy's children could actually get the "mutated" gene. This is especially true since Sheldon and Missy are twins. Also, since the episode is about who out of Leonard, Howard or Raj, Sheldon would allow to "mate" with his sister, there is the added "insurance" of getting any smart genes from any of the 3 Lothario's mentioned above.
If you are going to try to argue with a geneticist about genetics, please use the correct terms. Sheldon is not referring to a recessive gene - there is no such thing as a dormant gene - he is speaking of a randomly mutated gene. Those are the words he used. If he had inherited a homozygous recessive karotype - one recessive gene from each of his parents - then somewhere in his family tree there would similarly gifted people, in which case he would use the correct term - a recessive gene. If Missy is a heterozygotic dominant karotype possessing the recessive gene for super-genius and the dominant for ordinary intelligence then mating her with Howard, Raj or Leonard would be a waste of time as their dominant genius gene would prevent the recessive super-genius gene from being expressed in the phenotype of the resulting child. The child would be highly intelligent but not on Sheldon's standards. It doesn't matter if Sheldon does not know any of this as he refers several times to a randomly mutated gene, not a recessive one. Missy does not carry the super-genius gene. The posting is correct.
Sheldon is prone to magical thinking when necessary to preserve his obsessive need to control his environment. He may have simply ignored the flaw in his reasoning, as even the most intelligent humans do when venturing outside their ares of expertise. He may be interested in the science of genetics, but his Ph.D. in physics doesn't qualify him as an expert in that field.