SNP Array NOTE: THIS IS A SAMPLE REPORT AND MAY NOT REFLECT ACTUAL PATIENT DATA. FORMAT AND/OR CONTENT MAY BE UPDATED PERIODICALLY.

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1 SAMPLE REPORT SNP Array NOTE: THIS IS A SAMPLE REPORT AND MAY NOT REFLECT ACTUAL PATIENT DATA. FORMAT AND/OR CONTENT MAY BE UPDATED PERIODICALLY. RESULTS SNP Array Copy Number Variations Result: LOSS, Pathogenic (2p16.3) Regions of Homozygosity Result: Normal Male Change Chromosome Region Min Interval Min Size (Mb) Max Size (Mb) LOSS 2p ,848,099-50,901, SNP Array Result: arr[grch37] 2p16.3( _ )x1 INTERPRETATION COPY NUMBER VARIATIONS The results of this test indicate an interstitial copy number LOSS at 2p16.3. This copy number loss is a minimum of 53 kb and results in a partial deletion of NRXN1 from exons 6 to 8 (NM_ ). Partial copy losses involving the coding regions of NRXN1 gene of variable sizes, ranging from 14 kb to 1.15 Mb, have previously been reported. Heterozygous copy losses in NRXN1 have been reported in individuals with variable neurodevelopmental phenotypes, including intellectual disability, speech delay, autism spectrum disorders, ADHD, schizophrenia, seizures, and hypotonia (Bena, 2013; Ching, 2010; Dabell, 2013; Lal, 2015, Lowther, 2016). Short stature, macrocephaly, birth defects of the brain, and cardiac defects or dysfunction have also been reported in a small number of individuals with NRXN1 copy losses (Ching, 2010; Dabell, 2013). In reported cases, NRXN1 copy losses are often inherited from a parent, who may or may not be affected (Bena, 2013) and also documented in control populations, suggesting reduced penetrance (Kirov, 2014). Based on the gene content and supporting literature, this alteration is expected to be pathogenic. Clinical correlation is recommended. Microarray parental variant study is available for the 2p16.3 copy loss at no additional charge to determine whether this alteration is inherited or de novo. REGIONS OF HOMOZYGOSITY No regions of homozygosity were detected. Neurodevelopment-Expanded testing is in progress. The results of this analysis will be reported separately. Genetic counseling is a recommended option for all patients undergoing genetic testing. Laboratory Director: Trieu Timothy D. Vo, PhD, DABMG, FACMG. CLIA# 05D Page 1 of 5

2 Please note: Any tests on hold, previously reported, and those that have been cancelled (including reflex testing steps cancelled due to a positive result in a preceding test) have not been included in this report. For additional information, please contact Ambry Genetics. REFERENCES Bena F, et al. (2013) Am J Med Genet B Neuropsychiatr Genet 162B(4): Ching MSL, et al. (2010) Am J Med Genet B Neuropsychiatr Genet 153B(4): Dabell MP, et al. (2013) Am J Med Genet 161A(4): Kirov G, et al. (2014) Biol Psychiatry 75(5): Lal D, et al. (2015) PLoS Genet 11(5): e Lowther C, et al. (2017) Genet Med 19(1): REFSEQ GENES The 2p16.3 region contains 1 gene: NRXN1 ELECTRONICALLY SIGNED BY Sample Director, on 0/00/0000 at 0:00:00 PM Laboratory Director: Trieu Timothy D. Vo, PhD, DABMG, FACMG. CLIA# 05D Page 2 of 5

3 SNP ARRAY ASSAY INFORMATION (Supplement to Test Results) General Information: Genomic imbalances are an underlying cause of congenital anomalies, developmental delay, intellectual disability, autism, dysmorphism and numerous genetic syndromes. Routine karyotype analysis can detect some common chromosomal imbalances such as aneuploidies, but cannot detect smaller DNA rearrangements under 5 Mb. Chromosomal Microarray Analysis (CMA) via Array-based Comparative Genomic Hybridization (acgh) is a technique that allows for high resolution genome-wide detection of unbalanced structural and numerical chromosomal abnormalities. In addition, SNP probes are used to detect copy-neutral chromosomal changes, such as regions of homozygosity (ROH) the pattern of which may indicate uniparental disomy (UPD) or may suggest consanguinity and identity by descent. Importantly, the level of resolution of SNP Array depends only on the size and spacing of the oligonucleotide probes on the array. Methodology: Genomic deoxyribonucleic acid (gdna) is isolated from the patient s specimen using a standardized kit, quantified, labeled and hybridized to an oligonucleotide array with more than 1.9 million copy number probes and nearly 750,000 SNP probes used for genotyping and copy number analysis. This array allows for detection of loss of copy number (deletion), gain of copy number (duplication) or regions of homozygosity which may indicate uniparental disomy. FISH confirmation analysis, if requested, will be performed by CombiMatrix Diagnostics, 310 Goddard, Suite 150, Irvine, CA Analytical Range: The Ambry CMA: SNP Microarray (Affymetrix CytoScan HD Array, Santa Clara, CA) backbone probe spacing is set at an average of 1.1 kb throughout the entire human genome and an average of 880 basepairs in intragenic regions throughout the genome. Deletions and duplications with no known or suspected clinical relevance to the indication for testing, and regions seen frequently in control populations and documented in the Database of Genomic Variants may not be reported. The array detects currently known microdeletion/duplication syndromes, uniparental disomy due to isodisomy and most disorders detected by chromosomal analysis and FISH tests. Copy number neutral regions of homozygosity (ROH) greater than 10 Mb are reported, though this threshold may vary depending on the location and gene content of the ROH region. ROH comprising 2.5% or greater of the covered genome will be reported. Expected (Normal) Value: Diagnostic: No significant copy number changes or regions of homozygosity were detected. Family History or Carrier Screen: No significant copy number changes or regions of homozygosity were detected. Result Reports: Deletions and duplications of any size covering a known disease locus may be reported if determined to have potential clinical relevance. The copy number variant (CNV) location is reported by region and location on the chromosome, and includes the min/max size (Mb) of the span of loss or gain. Genomic coordinates corresponding to the minimum size (Min size Mb/kb) represents the distance between the first deviated proximal and distal probes of the CNV. Maximum size (Max size Mb/kb) represents the distance between the first non-deviated proximal and distal probes flanking the CNV. Array nomenclature is based on the ISCN (International System for Human Cytogenetic Nomenclature) 2016 guidelines. Analysis is based on genome assembly GRCh 37/hg19. CNVs in the following classifications are always reported, and are based on the following definitions: Pathogenic: CNV with sufficient evidence to classify as pathogenic (capable of causing disease). Likely Pathogenic: CNV with strong evidence in favor of pathogenicity. Uncertain Clinical Significance: CNV with limited and/or conflicting evidence regarding pathogenicity. Medical management to be based on personal/family clinical histories, not CNV carrier status. Variant, Likely Benign (VLB): CNV of compelling size containing genes without definitive role in clinically relevant disease Recessive disease states are not routinely reported, however well characterized disorders with high carrier population frequencies and disorders with potential clinical relevance may be reported. Clinical concern for recessive disease should be communicated to the laboratory for appropriate evaluation. Additional testing may be indicated to further characterize the alteration(s) identified. Parental analyses may be indicated to determine if the alteration(s) are de novo or inherited and to further characterize the origin of the alteration(s). Resources: The following references are used in copy number variation classification when applicable for observed alterations. 1. HGMD [Internet]: Stenson PD et al. Genome Med. 2009;1(1):13 World Wide Web URL: 2. Online Mendelian Inheritance in Man, OMIM. McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University (Baltimore, MD), Copyright World Wide Web URL: 3. DECIPHER database [Internet]: Bragin E, et al. Nucleic Acids Res 2014:42(Database issue):d993-d1000 World Wide Web URL: Laboratory Director: Trieu Timothy D. Vo, PhD, DABMG, FACMG. CLIA# 05D Page 3 of 5

4 4. Database of Genomic Variants: MacDonald JR, et al. Nucleic Acids Res Jan;42(Database issue):d World Wide Web URL: 5. UCSC Genome Browser: Kent WJ, et al. Genome Res Jun;12(6): World Wide Web URL: 6. ClinGen. Rehm H.L, et al. N Engl J Med (23): World Wide Web URL: Disclaimer: This test was developed and its performance characteristics were determined by Ambry Genetics Corporation. It has not been cleared or approved by the US Food and Drug Administration. The FDA does not require this test to go through premarket FDA review. It should not be regarded as investigational or for research. This test should be interpreted in context with other clinical findings. The Ambry Test: SNP Array will only detect net gain or loss of genomic material and regions of homozygosity (ROH) meeting reporting criteria and therefore is not intended to analyze the following types of chromosomal aberrations: balanced translocations, Robertsonian translocations, balanced insertions, inversions, point mutations, low level mosaicism, epigenetic abnormalities, heterodisomic or mosaic UPD or any microdeletions and duplications that are under the resolution of the array or not represented on the array. A negative result from the analysis cannot rule out the possibility that a tested individual carries an aberration in the undetectable group. Although molecular tests are highly accurate, rare diagnostic errors may occur. Possible diagnostic errors include sample mix-up, technical errors, and clerical errors. This report does not represent medical advice. Any questions, suggestions, or concerns regarding interpretation of results should be forwarded to a genetic counselor, medical geneticist, or physician skilled in interpretation of the relevant medical literature. This laboratory is certified under the Clinical Laboratory Improvement Amendments (CLIA) as qualified to perform high complexity clinical laboratory testing. HiddenText Laboratory Director: Trieu Timothy D. Vo, PhD, DABMG, FACMG. CLIA# 05D Page 4 of 5

5 SNP ARRAY RESULTS: arr[grch37] 2p16.3( _ )x1 Laboratory Director: Trieu Timothy D. Vo, PhD, DABMG, FACMG. CLIA# 05D Page 5 of 5