MRC-Holland MLPA. Description version 15;

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1 probemix P036-E1 HUMAN TELOMERE-3 Lot E1-0910, E1-1208, E As compared to version D2 (lot D2-0408), the probes for 1p and 4q have been replaced. Approximately 3-8% of all cases of mental retardation is caused by aberrant copy numbers of subtelomeric regions, e.g. due to unbalanced translocations. This P036-E1 human telomere-3 probemix contains one MLPA probe for each subtelomeric region and is designed to detect deletions/duplications of these subtelomeric regions. For the acrocentric chromosomes 13, 14, 15, 21 and 22, which contain primarily repeat sequences on their entire p-arms, we included a probe on the q arm, close to the centromere. Due to an increased frequency of copy number variable (cnv) regions close to the telomeres in healthy individuals, we strongly recommend to further investigate any abnormality detected, e.g. using our telomere follow up probemixes and by analysis of parental samples. More information is available on pages 4-7. At the p-telomeric ends of the X and Y chromosomes a region of approximately 2500 kb of DNA is identical in both sex chromosomes: the pseudoautosomal region 1, or PAR1. Similarly, the PAR2 region of approximately 800 kb at the q-telomeric ends is also identical for chromosome X and Y. The probes in these PAR regions will therefore show identical copy numbers in most males and females. Also included are two small synthetic MLPA probes for non-telomeric Y-chromosome specific sequences. This SALSA probemix is designed to detect deletions/duplications of one or more genes at the telomere ends in a human DNA sample. Heterozygous deletions of probe recognition sequences should give a 35-50% reduced relative peak area of the amplification product of that probe. Note that a mutation or polymorphism in the sequence detected by a probe can also cause a reduction in relative peak area, even when not located exactly on the ligation site! In addition, some probe signals are more sensitive to sample purity and small changes in experimental conditions. Therefore, deletions and duplications detected by MLPA should always be confirmed by other methods. Not all deletions and duplications detected by MLPA will be pathogenic. Users should always verify the latest scientific literature when interpreting their findings. The Database of Genomic Variants can be useful to verify whether copy number changes occur in normal individuals: A website with useful information on MLPA and FISH probe locations is SALSA probemixes and reagents are sold by for research purposes and to demonstrate the possibilities of the MLPA technique. They are not CE/FDA certified for use in diagnostic procedures. Purchase of the SALSA test probemixes and reagents includes a limited license to use these products for research purposes. The use of a SALSA probemix and reagents requires a thermocycler with heated lid and sequence type electrophoresis equipment. Different fluorescent PCR primers are available. The MLPA technique has been first described in Nucleic Acid Research 30, e57 (2002). Related SALSA probemixes More probemixes for specific subtelomere analysis are available (follow-up probemixes); see page 4-7. P070 Human telomere-5: contains a probe for every human subtelomere. Should be used together with the probemix P036 Human telomere-3. P069 Human telomere-4: Identical to P070 Human telomere-5, but does not contain probes for the acrocentric chromosome arms 13p, 14p, 15p, 21p and 22p. P245 Microdeletion: probes for 21 different microdeletion syndromes; can be used for primary screening of microdeletion syndromes. P064 MR-1/P096 MR-2: contains probes for several microdeletion syndromes P106 MRX: X-linked mental retardation More probemixes are available for specific syndromes, including RETT(-like) syndrome, DiGeorge, Prader- Willi/Angelman, Lissencephaly, Canavan, Williams syndrome and many more. Please see our website. More information Website : info@mlpa.com (information & technical questions); order@mlpa.com (orders) Mail : bv; Willem Schoutenstraat 6, 1057 DN Amsterdam, the Netherlands SALSA P036 Human telomere-3 Page 1 of 9

2 References of SALSA probemixes P036 & P070 (P069) Broad Telomere Screening A PubMed search on MLPA and telomere will provide more than 30 references. Ahn J. et al. (2007). Detection of subtelomere imbalance using MLPA: validation, development of an analysis protocol, and application in a diagnostic centre. BMC Medical Genetics Mar 5;8(1):9. Bruno D.L. (2006). High-throughput analysis of chromosome abnormality in spontaneous miscarriage using an MLPA subtelomere assay with an ancillary FISH test for polyploidy. Am J Med Genet A Dec 15;140(24): Darnfors C et al. (2005). High-resolution analysis of the subtelomeric regions of human embryonic stem cells. Stem Cells.; 23(4): Erjavec-Skerget A. (2006). Subtelomeric chromosome rearrangements in children with idiopathic mental retardation: applicability of three molecular-cytogenetic methods. Croat Med J Dec;47(6): Kirchhoff M. et al. (2005). Investigation of patients with mental retardation and dysmorphic features using comparative genomic hybridization and subtelomeric multiplex ligation dependent probe amplification. Am J Med Genet A Dec 15;139(3): Koolen DA et al. (2004). Screening for subtelomeric rearrangements in 210 patients with unexplained mental retardation using multiplex ligation dependent probe amplification (MLPA). J Med Genet.; 41(12): Lam AC et al. (2006) High rate of detection of subtelomeric aberration by using combined MLPA and subtelomeric FISH approach in patients with moderate to severe mental retardation. Clin Biochem. 39(3): Monfort S. et al. (2006). Evaluation of MLPA for the detection of cryptic subtelomeric rearrangements. J Lab Clin Med Jun;147(6): Northrop, EL et al. (2005). Detection of cryptic subtelomeric chromosome abnormalities and identification of anonymous chromatin using a quantitative multiplex ligation-dependent probe amplification (MLPA) assay. Hum. Mutat. 26 (5): Palomares, M. et al. (2006). MLPA vs multiprobe FISH: comparison of two methods for the screening of subtelomeric rearrangements in 50 patients with idiopathic mental retardation. Clin Genet Mar;69(3): Rooms, L. et al. (2006). Multiplex ligation-dependent probe amplification to detect subtelomeric rearrangements in routine diagnostics. Clin Genet Jan; 69(1): Data analysis The P036-E1 Telomere-3 probemix contains 46 MLPA probes with amplification products between 130 and 483 nt. In addition, it contains 10 control fragments generating amplification products smaller than 120 nt: four DNA Quantity fragments (Q-fragments) at nt, three DNA denaturation control fragments (D-fragments) at nt, one X-chromosome specific fragment at 100 nt and two chromosome Y- specific fragments at 105 & 118 nt. More information on how to interpret observations on these control fragments can be found in the MLPA protocol. Data generated by this probemix can be normalised intra-sample by dividing the peak area of each amplification product by the combined peak area of all peaks in that sample (global normalisation). Secondly, inter-sample normalisation can be achieved by dividing the intra-normalised probe ratio in a sample by the average intra-normalised probe ratio of all reference samples. Data normalisation should be performed within one experiment. Only samples purified by the same method should be compared. For broad telomere screening it is recommended to use SALSA probemixes P036 and/or P070 Human Telomere. Confirmation of most deletions can be done by one of the SALSA telomere follow-up probemixes (see page 5) or by another method, such as FISH, LR-PCR, southern blotting and sequencing. Note that Coffalyser, the MLPA analysis tool developed at, can be downloaded free of charge from our website Many copy number alterations in healthy individuals are described in the database of genomic variants: For example, a duplication of a complete gene might not be pathogenic, while a partial duplication or a deletion may result in disease. For some genes, certain in-frame deletions may result in a very mild, or no disease. Copy number changes of reference probes are unlikely to be the cause of the condition tested for. Users should always verify the latest scientific literature when interpreting their findings. This probemix was developed at. Info/remarks/suggestions for improvement: info@mlpa.com. SALSA P036 Human telomere-3 Page 2 of 9

3 Table 1. P036-E1 Human Telomere-3 probemix Length Chromosomal Gene detected (nt) position probe MapView build 36 position Q-fragments: DNA quantity; only visible with less than 100 ng sample DNA D-fragments: Low signal of 88 or 96 nt fragment indicates incomplete denaturation 100 X-fragment: Specific for the X chromosome 105 Y-fragment: Specific for the Y chromosome 118 Y-fragment: Specific for the Y chromosome 130 ± 1p TNFRSF L p ACP L p CHL L p PIGG (FLJ20265) L p PDCD L p IRF L p ADAP1 (CENTA1) L p FBXO L p DMRT L p DIP2C (KIAA0934) L p RIC8A (RIC-8) L ± 12p SLC6A L ± 13q-cen PSPC L (Acrocentric chromosome) q-cen CCNB1IP1 (HEI10) L (Acrocentric chromosome) q-cen MKRN L (Acrocentric chromosome) p POLR3K L p RPH3AL L p USP L ± 19p CDC L p SOX L q-cen RBM L (Acrocentric chromosome) q-cen BID L (Acrocentric chromosome) 298 Xp/Yp (PAR1) SHOX L01331 X/Y (PAR1 region) 307 1q SH3BP5L (KIAA1720) L (0.2 Mb from telomere) 313 2q CAPN L (1.6 Mb from telomere) 322 3q BDH L (0.7 Mb from telomere) 330 4q TRIML L (2.0 Mb from telomere) 337 5q GNB2L L (0.2 Mb from telomere) 346 6q PSMB L (0.5 Mb from telomere) 355 7q VIPR L (0.3 Mb from telomere) 361 8q ZC3H3 (KIAA0150) L (1.6 Mb from telomere) 372 9q EHMT L (0.2 Mb from telomere) q PAOX (PAO) L (0.2 Mb from telomere) q NCAPD3 (KIAA0056) L (1.2 Mb from telomere) q ZNF L (0.2 Mb from telomere) q F L (1.3 Mb from telomere) 411 ± 14q MTA L (1.3 Mb from telomere) 418 ± 15q ALDH1A L (1.0 Mb from telomere) q GAS8 (GAS11) L (0.2 Mb from telomere) q TBCD L (0.5 Mb from telomere) q RBFA (C18orf22) L (0.2 Mb from telomere) 450 ± 19q CHMP2A (BC-2) L (0.9 Mb from telomere) 458 ± 20q OPRL L (0.2 Mb from telomere) q PRMT2 (HMT1) L (0.1 Mb from telomere) q RABL2B L (0.1 Mb from telomere) 483 Xq/Yq (PAR2) VAMP7 (SYBL1) L02150 X/Y (PAR2; 0.1 Mb from telom.) Many notes on individual probes are present on page 7 and 8. New in version E1 (from lot E onwards) + The 13, 14, 15, 21 & 22 q-cen probes target the q arm close to the centromer (acrocentric chromosomes). ± This probe is located within, or close to, a very strong CpG island. A low signal of this probe can be due to incomplete sample DNA denaturation, e.g. due to the presence of salt in the sample DNA. Complete probe sequences are available on request: info@mlpa.com. Please notify us of any mistakes and of interesting findings: info@mlpa.com. SALSA P036 Human telomere-3 Page 3 of 9

4 Finding the genetic cause of mental retardation with MLPA The number of genes whose defect can result in mental retardation is large. In some cases, particular phenotypic features suggest the involvement of a specific gene or chromosomal region. Numerous SALSA MLPA probemixes are available to find the cause of mental retardation with distinct syndromic features, such as RETT, Sotos and Prader-Willi/Angelman syndrome. For patients suffering from non-syndromic mental retardation, the genetic cause is found only in a minority of cases. Usually, primary screening of these patients is done by karyotyping or G-banding. When no abnormality is detected by these methods, we suggest screening patients with the following probemixes: SALSA probemix P245 Microdeletion syndromes for 21 distinct microdeletion syndromes SALSA probemixes P036 Human telomere-3 and P070 Human telomere-5 for broad telomere screening Figure 1: Flowchart suggesting how to test a patient with mental retardation lacking clear syndromic features. SALSA probemix P245 Microdeletion syndromes P245 Microdeletion syndromes contains probes for 21 different microdeletion syndromes causing mental retardation. In case an abnormality is found with SALSA probemix P245 Microdeletion syndromes, we recommend further investigation using one of the microdeletion follow-up probemixes. See the P245 Microdeletion syndromes product description for details. SALSA probemix P036 Human telomere-3 and P070 Human telomere-5 Studies have indicated that 3-8% of all mental retardation cases are caused by aberrant copy numbers of subtelomeric regions (see references on p.2). SALSA probemixes P036 Human telomere-3 and P070 Human telomere-5 both contain one probe for each subtelomere and detect deletions/duplications in the subtelomeric regions. It is recommended to use both probemixes together to maximise the detection rate. Most probes in the P036 and P070 probemixes target well-characterised genes adjacent to the telomere. An exception is made for the p-arms of chromosomes 13, 14, 15, 21 and 22 as these are covered by over 10 Mb of repeat sequences. Here, the p probes recognise one of the first genes on the q arm, close to centromere. SALSA probemix P069 Human telomere-4 does not contain probes for these acrocentric arms. SALSA P036 Human telomere-3 Page 4 of 9

5 The detection of abnormal copy numbers in subtelomeric regions is complicated. Subtelomeric copy number changes can also occur in unaffected individuals and the effect of a deletion or duplication will depend on the genes involved. A considerable number of abnormalities detected by a single probe may not have a phenotypic effect but can be due to a rare polymorphism or a copy number change which is also present in one of the parents. For some chromosome arms, even large subtelomeric deletions (>1 Mb) can be inherited without a phenotypic effect; see the notes on p. 6 & 7. Abnormalities detected by our subtelomere probemixes will therefore not always be the cause of the mental retardation. For all abnormalities detected, we strongly recommend testing parents to determine whether the copy number aberration in the patient is de novo. De novo deletions/duplications have a higher probability of being the cause of the mental retardation. The Database of Genomic Variants can be useful to verify whether copy number changes occur in normal individuals: For the reasons mentioned above, the development of a perfect MLPA assay for the detection of subtelomeric deletions and duplications is complicated. Genes that are located very close to the telomeres have a higher chance of being polymorphic in copy number (i.e. duplicated/deleted in a small percentage of unaffected individuals, sometimes only in certain populations), whereas situating probes at a larger distance from the telomeres may lead to false negatives. Based on feedback from customers, we will try to further improve our telomere probemixes. New versions are therefore expected in the future. Follow-up When used correctly, MLPA will exclude the presence of abnormal copy numbers of subtelomeric regions in the majority of samples. However, no method will be capable of detecting all chromosomal aberrations. MLPA will not detect inversions or balanced translocations. Frequent microdeletion syndromes can be detected with the P245 Microdeletion syndromes probemix, but many rare interstitial deletions will not. In case an abnormality is detected by the P036 and/or P070, there are two ways to confirm the result: 1. Confirmation by another method, such as FISH, LR-PCR, Southern blot and sequencing. 2. Using a SALSA telomere follow-up probemix. Follow-up probemixes contain more probes per telomere and are suitable to examine a specific region more closely. Using an MLPA follow-up probemix will enable you both to confirm the presence of the aberration and determine its size. More detailed subtelomeric analysis For a closer examination of samples in which aberrant copy numbers have been found, the following MLPA probemixes are available. Subtelomeric region Subtelomeric region probemix probemix 1p (36 probes) P147 1p36 1q (14 probes) P264 telo-9 2p (13 probes) P208 telo-6 2q (12 probes) P264 telo-9 3p (11 probes) P208 telo-6 3q (11 probes) P264 telo-9 4p (16 probes) P358 telo-15 4q (8 probes) P264 telo-9 5p (6 probes) P358 telo-15 5q (13 probes) P277 telo-10 6p (12 probes) P208 telo-6 6q (10 probes) P277 telo-10 7p (10 probes) P365 telo-14 7q (10 probes) P277 telo-10 8p (12 probes) P208 telo-6 8q (10 probes) P277 telo-10 9p (12 probes) P230 telo-7 9q (13 probes) P286 telo-11 10p (11 probes) P230 telo-7 10q (8 probes) P286 telo-11 11p (7 probes) P230 telo-7 11q (14 probes) P286 telo-11 12p (11 probes) P230 telo-7 12q (9 probes) P286 telo-11 13q-cen (7 probes) P358 telo-15 13q (12 probes) P291 telo-12 14q-cen (7 probes) P358 telo-15 14q (10 probes) P291 telo-12 15q-cen (3 probes) P365 telo-14 15q (10 probes) P291 telo-12 16p (8 probes) P365 telo-14 16q (10 probes) P291 telo-12 17p (15 probes) P249 telo-8 17q (10 probes) P320 telo-13 18p (8 probes) P249 telo-8 18q (10 probes) P320 telo-13 19p (9 probes) P249 telo-8 19q (8 probes) P320 telo-13 20p (13 probes) P249 telo-8 20q (7 probes) P320 telo-13 SALSA P036 Human telomere-3 Page 5 of 9

6 Subtelomeric region Subtelomeric region probemix probemix 21q-cen (4 probes) P365 telo-14 21q (9 probes) P365 telo-14 22q-cen (19 probes) P356 Chr. 22q 22q (17 probes) P356 Chr. 22q To make a more detailed screening of all chromosomes easier, an attractively-priced Telomere Follow-up Set containing 25 reactions of each of the 12 telomere follow-up probemixes is available for an introduction price of 1200 euro in It is also possible to order each follow-up probemix separately (25, 50 or 100 reactions). Important notes on specific telomeres Please inform us about any mistakes or interesting findings: info@mlpa.com. All complete probe sequences are available on request: info@mlpa.com. 1p: The P036-E probemix contains a new probe for 1p (TNFRSF4 gene). The 1p probe in P036-D (SCNN1D) gave variable results and the 1p probe in P036-B (CAB45) was found to be deleted or duplicated in some healthy families. The P069/P070 probe for 1p detects a sequence that has been found to be duplicated in a normal individual (K. Claes, Ghent). As deletions of this region may have consequences, we will not replace this probe. 2p: The P036 probe for 2p has been found to be deleted in several healthy persons in Nijmegen (E. Sistermans) and Maastricht. We do not know whether this is due to a polymorphism in the Dutch population. In case deletions in healthy persons also occur elsewhere, this probe will be replaced in the future. Please inform us on aberrant results. 3p: The P036/P069/P070 probes for 3p (CHL1 gene) were found to be duplicated in healthy parents (J. Wook Ahn, London and E. Sistermans, Nijmegen). In another family, a deletion of the P036 and P069- P070 probes for 3p was detected in a healthy parent (J. Wook Ahn, London). According to Dijkhuizen et al (2006; Am.J.Hum.Genet. 140A, ), defects in the more centromeric CNTN4 and CRBN genes might be more important for the 3p syndrome than CHL1 loss. 5p: The P036 probe for 5p was found to be duplicated in two healthy parents (F. Jehee, Sao Paulo). 9p: The P069/P070 probes for 9p (DOCK8 gene) were found to be duplicated in a healthy parent in four different families by J. Wook Ahn (London). In one other family, a deletion of this probe was detected in a healthy parent (same lab). 11p: The P036/P069/P070 probes for 11p detect sequences that have been found to be duplicated in sporadic cases in a normal individual (M. Palomares Bralo, Madrid). As deletions of this region might well have consequence, we will not replace this probe. 12p: The P036/P069/P070 probes detect sequences that were found to be duplicated in a healthy parent in one Brazilian family (F. Jehee, Sao Paulo). In two other families, a deletion of the P036 probe was detected in a healthy parent (same lab) while the P070 probe for 12p was normal. 13q-cen: This probe detects sequences on the q-arm, close to the centromere, as the p-arm of this chromosome does not contain well-characterised genes. 14q-cen: This probe detects sequences on the q-arm close to the centromere, as the p-arm of this chromosome does not contain well-characterised genes. 15q-cen: This probe detects sequences on the q-arm close to the centromere, as the p-arms do not contain well-characterised genes. The P036 probe for 15q-cen detects the MKRN3 gene (234 nt). This region is deleted in some Prader-Willi/Angelman syndrome patients. The PWS/AS critical region (SNRPN gene) is located at a distance of 1.3 Mb towards the q-telomere. We recommend the SALSA probemix ME028 Prader-Willi/Angelman for further characterisation of copy number changes of the MKRN3 region. 16p: In several Brazilian families a deletion of the P036 probe for 16p was detected in a healthy parent, while the P070 probe showed normal results (F. Jehee, Sao Paulo). 20p: The P036/P069/P070 probes for 20p detect sequences that have been found to be duplicated in sporadic cases in a normal individual (V. Biancalana; Strasbourg). As deletions of this region might have consequences, we will not replace this probe. 21q-cen: This probe detects sequences on the q-arm close to the centromere, as the p-arm of this chromosome does not contain well-characterised genes. 22q-cen: This probe detects sequences on the q-arm close to the centromere, as the p-arm of this chromosome does not contain well-characterised genes. SALSA P036 Human telomere-3 Page 6 of 9

7 3q: The P036 probe for 3q (BDH gene) was found to be duplicated in a healthy parent by E. Reyniers, Antwerp (confirmed by FISH). The P070/P069 probe for 3q, located 200 kb closer to the telomere, did not show this duplication. Apparently, copy number polymorphisms of the BDH gene region occur in healthy individuals. However, please note that a 3q29 microdeletion syndrome (due to an interstitial deletion) has been described (Willatt et al, J. Hum. Genet. 77: , 2005) and that the probe in the P036 probemix detects a sequence within this commonly deleted region. The 3q probe in P070 will not detect this microdeletion, as it detects a sequence located between the interstitial deletion and the telomere. 4q: The P036-E probemix contains a new probe for 4q. The 4q telomeric region is complicated and very few genes are present. The FRG1 gene is the only well-characterised gene in the terminal 2-3 Mb of 4q, but the FRG1-specific probes in P036-B, P036-C and P036-D were found to be unreliable due to the presence of population-specific SNPs in FRG1. The 4q probe in P036-E is located at larger distance from the telomere; we do not expect this to cause many false-negative results as deletions of the telomeric 2-3Mb region of 4q do not seem to cause any phenotypic effects (Shao, L. et al (2008) Am. J. Med. Genet.). 5q: The P036 probe for 5q was found to be influenced in one patient by a polymorphism in the first nucleotide after the ligation site by K. Franke (Dresden). Please report similar findings as probes influenced by polymorphisms will be replaced. The P036/P069/P070 probes for 5q detect sequences that have been found to be duplicated in sporadic cases in a normal individual (K. Mann, London, L. Rooms & S. Seneca, Antwerp). As deletions of this region may have consequences, we will not replace this probe. 12q: A Dutch lab detected a ZNF10 duplication in a healthy parent with both the P036 and P070. ZNF10 is described as variable in copy number (Database of Genomic Variants, 17q: A duplication of the P069/P070 probe was detected in a healthy parent (F. Jehee, Sao Paulo). 19q: The P036/P070 probe for 19q gave variable results in healthy controls (F. Grati, Italy, and J. W. Ahn, UK). 22q: The P070 probe for 22q was found to be deleted in one healthy parent (F. Jehee, Sao Paulo). The sequence detected by the P036 probe for 22q has only one mismatch with a related sequence on chromosome 2. This is sufficient to generate a chr. 22q specific MLPA signal. However, when this region is to be sequenced, primer design is complicated. Only 4 mismatches are present in the 350 nt region containing this probe sequence. The P188 probe set contains many probes close to the 22q13 telomere and can be used to confirm or further characterise 22q13 deletions. X, Y: The 298 & 483 probes in P036/P069/P070 detect sequences located on both X & Y chromosome close to the telomeres (PAR region) and will thus indicate the combined copy number of X and Y. Differences between P036-D and P036-E The 1p and 4q probes have been replaced. Differences between P036-B and P036-E 1. The CAB45 probe for 1p36 has been replaced in P036-E by a probe for the TNFRSF4 gene. 2. The FRG1 probe for 4q has been replaced in P036-E by a probe for the TRIML2 gene. 3. The P036-B probe for 9q has been replaced in P036-E by a probe for the EHMT1 gene. 4. The CYFIP1 probe for 15p in P036-B was located in a polymorphic region and has been replaced by a MKRN3 probe in P036-E. 5. The 379 nt probe for 10q and the 450 nt probe for 19q have been recloned and have higher signals in P036-E as compared to P036-B. Length of these probes has been slightly altered but the sequences detected have remained identical. 6. Extra control fragments specific for the X and Y-chromosome have been included at 100 and 105 nt. SALSA P036 Human telomere-3 Page 7 of 9

8 probemix P036-E1 sample picture D y e S i g n a l Size (nt) Figure 2. Capillary electrophoresis pattern from a sample of approximately 50 ng human male control DNA analysed with probemix P036-E1 Human Telomere-3 (lot E1-0910). The old MLPA buffer (replaced in December 2012) was used. Vials with the old MLPA buffer have a white label D y e S i g n a l Size (nt) Figure 3. Capillary electrophoresis pattern from a sample of approximately 50 ng human male control DNA analysed with probemix P036-E1 Human Telomere-3 (lot E1-0910). The new MLPA buffer (introduced in December 2012) was used. Vials with the new MLPA buffer have a yellow label. SALSA P036 Human telomere-3 Page 8 of 9

9 Implemented Changes compared to the previous product description version(s). Version 15 (48) - Warning added in Table 1, 130 nt probe L01761, 208 nt probe L01767, 219 nt probe L01847, 265 nt probe L01313, 411 nt probe L02201, 418 nt probe L01295, 450 nt probe L10626, and 458 nt probe L Version 14 (48) - Electropherogram pictures using the new MLPA buffer (introduced in December 2012) added. Version 13 (48) - Various textual changes. - The C18orf22 gene name changed into RBFA in Table 1. Version 12 (46) - Information about the Telomere Follow-up Set has been added. Version 11 (46) - Wrong gene name corrected (RIC8B to RIC8A). Version 10 (44) - Product description adapted to a new lot (lot number added, small changes in Table 1 and Table 2, new picture included). - Small changes of probe lengths in Table 1 and 2 in order to better reflect the true lengths of the amplification products. - Minor changes in the product description on page 1. - Several genes have a new name (HUGO gene name standardization) Version 09 (45) - Notes on the 5p, 12p, 16p, 17q, and 22q probes added in the important notes on specific telomers section. Version 08 (45) - Remark on page 6 about the old 4p probe in P070 Telomere has been removed. Version 07 (44) - Minor changes in the product description on page and the data analysis section on page 2. - Gene names in table 1 updated. Version 06 (43) - Table number added to Table 1. - Extra note added under Table 1 referring to the notes on p. 6 and 7 - Extra note added under Table 1 about probes for acrocentric chromosomes - Note on 12q (ZNF10) probe added on p Table about MLPA follow-up mixes updated - Text Finding the cause of mental retardation made more concise - Text on data analysis has been clarified by using slightly different wording - Various minor textual changes on page 1, various minor layout changes. SALSA P036 Human telomere-3 Page 9 of 9