Molecular Analysis of CYP21A2 Gene Mutations among Iraqi Patients with Congenital Adrenal Hyperplasia

Table 6

Frequency of common allelic mutations in this study compared with previous studies from some of the neighboring and Arab countries.

	Present study, Iraq, 2015	Turkey, 2009 [10]	Jordan, 2011 [11]	Iran, 2011 [12]	Iran, 2008 [13]	Tunisia, 2004 [14]
Total alleles ()	124	91	92	88	100	102
Not detected (%)	39.5%	15.4%	40%	0	30%	5.9%
Molecular method(s) used	AS-PCR with reverse hybridization for 11 mutations	SB, AS-PCR/ER, and sequencing	ARMS for 8 common mutations & MLPA	AS-PCR for 8 common mutations and sequencing	AS-PCR for 8 mutations	ER + sequencing
P30L	0	0	17.8	0	0	0
I2Splice	14.5	22.0	35.7	14.77	28	17.6
Del 8 bp E3	3.2	4.4	16	0	13	0
I172N	8.1	9.9	16	5.68	9.0	10.8
Cluster E6	0	2.2	1.7	2.27	4.0	0
V281L	4.0	7.6	0	1.14	3.0	0
L307fs	0	0	NT	0	NT	0
Q318X	11.3	3.3	23.2	15.91	9	35.3
R356W	0	8.8	3.5	7.95	5.0	2.0
P453S	0.81	2.2	NT	NR	NT	NR
R483P	0.81	NR	NT	NR	NT
Deletions/conversions	19.3	8.8/14.3	0	31.8	NT	19.6

NR: not reported; NT: not tested; SB: southern blot; AS-PCR: allele-specific oligonucleotide hybridization by PCR; ER: enzyme restriction; ARMS: amplification refractory mutational screen; MLPA: multiplex ligation dependent probe amplification.