Sudden Sensorineural Hearing Loss and Polymorphisms in Iron Homeostasis Genes: New Insights from a Case-Control Study

Table 3

Hearing loss severity score stratified by different genotypes among the different gene variants: 44 (mild), 92 (moderate), 33 (severe), and 31 (profound). HL severity score is graded in the following: mild hearing loss (16–40 dB HL), moderate hearing loss (41–70 dB HL), severe hearing loss (71–90 dB HL), and profound hearing loss (>90).

Gene variant	FPN1 (SLC40A1)			Tf			HFE			HFE		HEPC (HAMP)
	−8CG			C1, C2			H63D			C282Y		−582AG
Cases	200			200			200			200		200
Genotypes	CC	CG	GG	C1C1	C1C2	C2C2	HH	HD	DD	CC	CY	AA	AG	GG
Total ()	123	62	15	139	53	8	142	56	2	193	7	111	77	12
HL severity score (PTA dB HL)
16–40 dB HL	27	12	5	27	16	1	31	13	0	42	2	34	6	4
41–70 dB HL	60	26	6	66	24	2	62	28	2	88	4	51	35	6
71–90 dB HL	18	12	3	21	8	4	25	8	0	32	1	12	19	2
>90 dB HL	18	12	1	25	5	1	24	7	0	31	0	14	17	0