Table 2.

TCOF1 mutations in TCS

Exon/nucleotide	Amino acid	Screening method	Case*
5	H141Q†	ASO‡	1F
422insA	STOP at 33 aa away	ATGCCACAACCCTGCCAC 62
		ATGCCACACCCTGCCAC 60
5	N166I†	ASO‡	1U
497delATAC	STOP at 48 aa away	TCAGCAATACGTTGGTCT 48
		TCAGCAAATACTACGTTG 45
10	S470Q†	ASO‡	2F
1408delAG	STOP at 1 aa away	CAGAGCAGTAGTGAGGAG 48
		CAGAGAGCAGTAGTGAGGAG 53
16	PR830–831PG§	ASO‡	1F
2490delC	STOP at 42 aa away	CCAAGGAGTCCCCAGGAA 53
		CCAAGGAGTCCCCCAGGAA 55
16	TG842–843TA§	Eco0109I (nl)¶	1F
2526delAG	STOP at 11 aa away
16 2552delA and 2561delA	K851S‖ STOP at 13 aa away	ASO for 2552delA‡ CAGGCAGGGAGCAGGA 48 CAGGCAGGGAAGCAGG 48 SfaNI for 2561delA	1S
16 2565delAG	SG855–856SE§ STOP at 9 aa away	DdeI (nl)¶	1F, 1S

ins, insertion; del, deletion; STOP, termination codon; aa, amino acid. 

^*The number of familial (F) and sporadic (S) cases in which mutations occurred is designated. If it is unknown whether a case is familial or sporadic because relatives are unavailable, it is designated as U. 

^†The amino acid change indicates the first amino acid that is substituted. All subsequent amino acids are changed as a result of the frameshift. 

^‡ASO primer sequences in 5′ to 3′ orientation are listed with T_m °C used to wash membranes. The top oligonucleotide hybridizes to the mutant sequence and bottom oligonucleotide hybridizes to the normal sequence. 

^§The amino acid change indicates (i) the amino acid in which a frameshift occurred without substitution and (ii) the next amino acid that is substituted. All subsequent amino acids are changed as a result of the frameshift. 

^¶Restriction enzymes used to detect mutant sequences are listed. (nl) indicates that the enzyme digests the normal, not the mutant sequence. 

^‖The amino acid change indicates the result of both mutations in the same gene.