Noriko Miyake, Yoshinori Tsurusaki, Ryoko Fukai, Itaru Kushima, Nobuhiko Okamoto, Kei Ohashi, Kazuhiko Nakamura, Ryota Hashimoto, Yoko Hiraki, Shuraku Son, Mitsuhiro Kato, Yasunari Sakai, Hitoshi Osaka, Kimiko Deguchi, Toyojiro Matsuishi, Saoko Takeshita, Aviva Fattal-Valevski, Nina Ekhilevitch, Jun Tohyama, Patrick Yap, Wee Teik Keng, Hiroshi Kobayashi, Keiyo Takubo, Takashi Okada, Shinji Saitoh, Yuka Yasuda, Toshiya Murai, Kazuyuki Nakamura, Shouichi Ohga, Ayumi Matsumoto, Ken Inoue, Tomoko Saikusa, Tova Hershkovitz, Yu Kobayashi, Mako Morikawa, Aiko Ito, Toshiro Hara, Yota Uno, Chizuru Seiwa, Kanako Ishizuka, Emi Shirahata, Atsushi Fujita, Eriko Koshimizu, Satoko Miyatake, Atsushi Takata, Takeshi Mizuguchi, Norio Ozaki, Naomichi Matsumoto
European journal of human genetics : EJHG 2023年3月27日
Autism spectrum disorder (ASD) is caused by combined genetic and environmental factors. Genetic heritability in ASD is estimated as 60-90%, and genetic investigations have revealed many monogenic factors. We analyzed 405 patients with ASD using family-based exome sequencing to detect disease-causing single-nucleotide variants (SNVs), small insertions and deletions (indels), and copy number variations (CNVs) for molecular diagnoses. All candidate variants were validated by Sanger sequencing or quantitative polymerase chain reaction and were evaluated using the American College of Medical Genetics and Genomics/Association for Molecular Pathology guidelines for molecular diagnosis. We identified 55 disease-causing SNVs/indels in 53 affected individuals and 13 disease-causing CNVs in 13 affected individuals, achieving a molecular diagnosis in 66 of 405 affected individuals (16.3%). Among the 55 disease-causing SNVs/indels, 51 occurred de novo, 2 were compound heterozygous (in one patient), and 2 were X-linked hemizygous variants inherited from unaffected mothers. The molecular diagnosis rate in females was significantly higher than that in males. We analyzed affected sibling cases of 24 quads and 2 quintets, but only one pair of siblings shared an identical pathogenic variant. Notably, there was a higher molecular diagnostic rate in simplex cases than in multiplex families. Our simulation indicated that the diagnostic yield is increasing by 0.63% (range 0-2.5%) per year. Based on our simple simulation, diagnostic yield is improving over time. Thus, periodical reevaluation of ES data should be strongly encouraged in undiagnosed ASD patients.