 This letter is then followed by an M , for "multiply inverted . "  The M is followed by a number to distinguish balancers of the same chromosome.
<fluency>  This letter is then followed by an M , for "multiply inverted . "  The M is followed by a number to distinguish balancers of the same chromosome.
 This letter is then followed by an M for "multiply inverted . " The M is followed by a number to distinguish balancers of the same chromosome.