
The Electric Can Opener Fluctuation - S3-E1
Continuity mistake: Sheldon's Sandwich goes from looking burnt to not burnt in the next few frames. (00:16:56)

The Cooper-Nowitzki Theorem - S2-E6
Continuity mistake: When Raj says there is always a catch, Leonard's hand goes from on the table to on his leg between camera cuts. (00:03:00)

The Griffin Equivalency - S2-E4
Continuity mistake: When talking to his parents, Raj's grip on the laptop changes between shots. Note the side of the screen. (00:18:10)

The Barbarian Sublimation - S2-E3
Continuity mistake: When Penny is talking to Sheldon in his bedroom, her hands are constantly changing positions between shots. (00:08:45)

Continuity mistake: When Sheldon is looking at his socks that Penny paired up, his grip on them changes between shots. (00:06:00)

Continuity mistake: Penny throws Sheldon's sock down on the table, and their positions change when Sheldon picks them up, despite no one touching them. (00:05:50)

Continuity mistake: When Leonard shows Penny the leaflet at the end, she is holding it in one hand in shot but with 2 as the camera changes. (00:19:50)

Continuity mistake: Leonard says that Sheldon has gone crazy and chucks his pen down on a red pad on the desk. When the shot changes, so does the position of the pen without being touched. (00:13:10)

Continuity mistake: In the laundry room, Sheldon is holding a blue shirt in his hands and has a bit of extra material near his hands. When the shot changes, he is holding the shirt differently and the extra material has gone. (00:05:50)

The Extract Obliteration - S6-E6
Continuity mistake: Sheldon is sitting by himself at a lunch table with an opened bottle of water with the bottle cap in front of the bottle. Raj and Howard arrive, and in one of the shots, the bottle cap moves closer to the bottle by itself.

The Grasshopper Experiment - S1-E8
Deliberate mistake: At the end, Penny holds up a bottle of rum to show Leonard that she added it to his drink. However, the B is missing from the name "Bacardi" (00:19:30)

The Big Bran Hypothesis - S1-E2
Continuity mistake: At the very end of the episode we see Penny with her hands on the corner of the piece of wood. Camera cut and now they are in the middle. (00:19:50)

The Big Bran Hypothesis - S1-E2
Continuity mistake: When cleaning Penny's apartment, Sheldon is holding up a jacket. Camera cuts and he is no longer holding the jacket up. (00:09:50)

The Big Bran Hypothesis - S1-E2
Continuity mistake: When Sheldon says the line about having no peers when cleaning the apartment, there is a pair of jeans on the side which disappears when the camera cuts. (00:10:00)

The Big Bran Hypothesis - S1-E2
Continuity mistake: When Sheldon is cleaning, he moves an iPod dock and the iPod lights up. Camera changes and the iPod is unlit. A few shots later it's lit again. (00:09:00)

The Big Bran Hypothesis - S1-E2
Continuity mistake: When shifting the box along the floor of the 3rd floor landing, Leonard's grips on the box is constantly changing. (00:06:00)
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.