beginning after December 31, 2017. 1102. Repeal of nonrefundable credits (a) Repeal of section 22 (1) In general Subpart A of part IV of subchapter A of chapter 1 is amended by striking section 22 (and by striking the item relating to such section in the table of sections for such subpart). (2) Conforming amendment (A) Section 86(f) is amended by striking paragraph (1) and by redesignating paragraphs (2), (3), and (4) as paragraphs (1), (2), and (3), respectively. (B) (i) Subsections (c)(3)(B) and (d)(4)(A) of section 7706, as redesignated by this Act, are each amended by striking (as defined in section 22(e)(3) . (ii) Section 7706(f), as redesignated by this Act, is amended by redesignating paragraph (7) as paragraph (8) and by inserting after paragraph (6) the following new paragraph: (7) Permanent and total disability defined An individual is permanently and totally disabled if he is unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment which can be expected to result in death or which has lasted or can be expected to last for a continuous period of not less than 12 months. An individual shall not be considered to be permanently and totally disabled unless he furnishes proof of the existence thereof in such form and manner, and at such times, as the Secretary may require. . (iii) Section 415(c)(3)(C)(i) is amended by striking 22(e)(3) and inserting 7706(f)(7) . (iv) Section 422(c)(6) is amended by striking 22(e)(3) and inserting 7706(f)(7) . (b) Termination of section 25 Section 25, as amended by section 3601, is amended by adding at the end the following new subsection: (k) Termination No credit shall be allowed under this section with respect to any mortgage credit certificate issued after December 31, 2017. . (c) Repeal of section 30D (1) In general Subpart B of part IV of subchapter A of chapter 1 is amended by striking section 30D (and by striking the item relating to such section in the table of sections for such subpart). (2)