Mild Phenotype: Causes & Reasons

Possible Causes for Mild Phenotype

Glutamate Formiminotransferase Deficiency

Features of a mild phenotype include high urinary excretion of FIGLU in the absence of histidine administration, mild developmental delay, and no hematological abnormalities [ncbi.nlm.nih.gov]

There are two forms of the disorder: a severe phenotype and a mild phenotype. [egl-eurofins.com]

Features of a severe phenotype, include elevated levels of formiminoglutamate (FIGLU) in the urine in response to histidine administration, megaloblastic anemia, and mental [uniprot.org]

Leydig Cell Hypoplasia due to LHB Deficiency

Females with inactivating mutations in the LHCGR gene display a mild phenotype characterized by defective follicular development and ovulation, amenorrhea, and infertility [ncbi.nlm.nih.gov]

Type II, a milder form caused by partial inactivation of the gene, displays a broader range of phenotypic expression ranging from micropenis to severe hypospadias. [ncbi.nlm.nih.gov]

Sarcotubular Myopathy

* Most patients have a mild phenotype, with limb-girdle weakness and a waddling gait at presentation. [checkorphan.org]

In our family, the phenotype encompasses additionally a mild demyelinating polyneuropathic syndrome. [ncbi.nlm.nih.gov]

Interestingly, heterozygous family members carrying only one mutation showed mild clinical symptoms and vacuolar changes in muscle. [ncbi.nlm.nih.gov]

Monosomy 21q

All three patients had relatively mild phenotypes. [jhu.pure.elsevier.com]

Mild Phenotypic Manifestations of Terminal Deletion of the Long Arm of Chromosome 4: Clinical Description of a New Patient. A Caliebe et al., Clin Genet. [rarediseases.org]

In contrast to previous observations, we showed that deletions of the 21q proximal region are not necessarily associated with severe phenotypes and, therefore, that mild phenotypes [molecularcytogenetics.biomedcentral.com]

Congenital Myopathy with Excess of Thin Filaments

Google Scholar | Crossref | Medline | ISI Jungbluth H., Sewry CA, Brown SC, et al: Mild phenotype of nemaline myopathy with sleep hypoventilation due to a mutation in the [journals.sagepub.com]

Mild phenotype of nemalinemyopathy with sleep hypoventilation due to a mutation in theskeletal muscle alpha-actin (ACTA1) gene. Neuromuscul Dis-ord 2001;11:3540.15. [documents.tips]

Clinical analyses revealed that the case described in the present study exhibited a relatively mild phenotype with regards to muscle weakness, as compared with more severe [spandidos-publications.com]

Aromatic L-Amino Acid Decarboxylase Deficiency

On the other hand, patients with a mild phenotype with AADC deficiency have been reported, but they number only a few cases. [x-mol.com]

Two patients in our institution have extremely mild phenotypes and their robust response to treatment illustrates the variable severity of this condition and the need for [go.gale.com]

Therefore, the variation of phenotypes of the disease appears to be broad, and it may be challenging to diagnose an atypical phenotype as AADC deficiency. [x-mol.com]

Isovaleric Acidemia

So more than half of IVA patients represent a new mild phenotype and potentially remain asymptomatic. [e-imd.org]

[…] associated with heterogeneous IVD gene mutations, and patients with a metabolically mild phenotype associated with the recurring mutation, 932C>T (A282V). [e-imd.org]

Moreover, with the application of MS/MS in newborn screening, potentially asymptomatic patients with one recurring IVD gene mutation and a mild biochemical phenotype are being [e-imd.org]

Cornelia De Lange Syndrome

[…] and major malformations are typical of the mild phenotype. [ncbi.nlm.nih.gov]

Curiously, the study of fibroblasts of two siblings with a mild CdLS phenotype and a pathological variant specific of the isoform A of NIPBL (c.8387A > G; P.Tyr2796Cys), showed [ncbi.nlm.nih.gov]

SMC1A and SMC3 mutations are responsible for a mild phenotype of the syndrome. [ncbi.nlm.nih.gov]

Trisomy 18p

Pure trisomy of the whole arm of chromosome 18 (18p), has been described in only a few cases and the general consensus is that there is a mild phenotypic effect. [ncbi.nlm.nih.gov]

At autopsy, the proband displayed a mild phenotype of hypertelorism, a small mouth, micrognathia, a narrowly arched palate, low-set ears, and clinodactyly. [ncbi.nlm.nih.gov]

Pure trisomy of the whole arm of chromosome 18 (18p), has been described in only a few cases and the general consensus is that there is a mild phenotypic… CONTINUE READING [semanticscholar.org]

3q29 Microdeletion

The phenotype includes mild-to-moderate mental retardation, with only slightly dysmorphic facial features that are similar in most patients: a long and narrow face, short [research.manchester.ac.uk]

The clinical phenotype is variable despite an almost identical deletion size. [research.manchester.ac.uk]

Cholesterol Ester Storage Disease

Markus Exner, Thomas Helbich, Clemens Dejaco, Gerd Schmitz, Peter Ferenci, A novel variant of lysosomal acid lipase in cholesteryl ester storage disease associated with mild [onlinelibrary.wiley.com]

[…] lipolytic enzymes of medical interest. 61 Roussel A...Cambillau C 10358049 1999 35 A novel variant of lysosomal acid lipase in cholesteryl ester storage disease associated with mild [malacards.org]

mild form of CESD. [ncbi.nlm.nih.gov]

Craniofrontonasal Dysplasia

Contrary to most X-linked disorders, females are much more severely affected whereas males are asymptomatic or present with a mild phenotype, frequently only displaying hypertelorism [orpha.net]

We suggest that this individual does have the CFND mutation, but has an extremely mild phenotype that is not detectable with clinical examination. [ncbi.nlm.nih.gov]

Triglyceride Storage Disease Type 2

[…] clinical phenotype of Tangier disease. [malattierare.regione.veneto.it]

[…] clinical phenotype of Tangier disease ATHEROSCLEROSIS-. [malattierare.regione.veneto.it]

Cusano-R; Cantafora-A; Calabresi-L; Franceschini-G; Ravazzolo-R; Calandra-S A point mutation in ABC1 gene in a patient with severe premature coronary heart disease and mild [malattierare.regione.veneto.it]

Chromosome 19q Duplication

This is similar to the case reported by Quack et al4 where the phenotype of both mother and child is mild. [jmg.bmj.com]

A rare case of a de novo dup(19q) associated with a mild phenotype. J Med Genet. 2002; 39:E61. 6. Zung A, Rienstein S, Rosensaft J, Aviram-Goldring A, Zadik Z. [synapse.koreamed.org]

A rare case of a de novo dup(19q) associated with a mild phenotype. J Med Genet. 2002;39(10):E61. [PMC free article] [PubMed] [Google Scholar] 4. [ncbi.nlm.nih.gov]

Triglyceride Storage Disease Type 1

[…] clinical phenotype of Tangier disease. [malattierare.regione.veneto.it]

[…] clinical phenotype of Tangier disease ATHEROSCLEROSIS-. [malattierare.regione.veneto.it]

Mild Androgen Insensitivity Syndrome

The clinical phenotype associated with MAIS is a normal male habitus with mild spermatogenic defect and / or reduced secondary terminal hair. [artsandculture.google.com]

[…] female, mild androgen insensitivity syndrome is indicated when the external genitalia is phenotypically male, and partial androgen insensitivity syndrome is indicated when [artsandculture.google.com]

[…] into three categories that are differentiated by the degree of genital masculinization: complete androgen insensitivity syndrome is indicated when the external genitalia is phenotypically [artsandculture.google.com]

Osteopathia Striata-Cranial Sclerosis

Affected Males There appear to be two distinct phenotypes in males: mild and severe. Mild phenotype. [ncbi.nlm.nih.gov]

Males can present with a mild or severe phenotype. [ncbi.nlm.nih.gov]

Males with the mild phenotype may have a mosaic or constitutional AMER1 pathogenic variant, each with distinct radiographic features. [ncbi.nlm.nih.gov]

Dominant GDAP1 mutations cause predominantly mild CMT phenotypes. Neurology. 2011;77:540–8. [ncbi.nlm.nih.gov]

L239F founder mutation in GDAP1 is associated with a mild Charcot-Marie-Tooth type 4C4 (CMT4C4) phenotype. Neurogenetics. 2010;11:357–66. [ncbi.nlm.nih.gov]

Chromosome 18 Pericentric Inversion

Prontera et al. (2010) stated that this was the first observation of familial transmission of a rec dup(18q), showing that this recombinant is associated with a mild phenotype [omim.org]

The dup(18q)/del(18p) recombinant patient with the milder phenotype, the one with the smallest structural aneuploidy, shared partly the mild clinical phenotype in the patients [nature.com]

phenotypic findings and behavioral problems.18, 19 The first offspring of the family described in this study is a further case of dup(18q)/del(18p), with very mild dysmorphic [ncbi.nlm.nih.gov]

Marfanoid Joint Hypermobility Syndrome

Occipital horn syndrome and a mild Menkes phenotype associatedwith splice sitemutations at the MNK locus. Nat Genet 1994; 8:195–202. [link.springer.com]

Marfanoid Habitus - Inguinal Hernia - Advanced Bone Age

Occipital horn syndrome and a mild Menkes phenotype associatedwith splice sitemutations at the MNK locus. Nat Genet 1994; 8:195–202. [link.springer.com]

Trisomy 3q2

[…] from a mild phenotype presenting joint pain and laxity, mild facial dysmorphism (e.g. long facies, prominent eyes, dysplastic ears, downturned corners of the mouth, micrognathia [orpha.net]

[…] variability ranging from a mild phenotype presenting joint pain and laxity, mild facial dysmorphism (e.g. long facies, prominent eyes, dysplastic ears, downturned corners [rarediseases.info.nih.gov]

Partial trisomy 3q causing mild Cornelia de Lange phenotype. J Med Genet. 1994;31:150-152. Ismail SR, et al. Duplication 3q (q21-qter) without limb anomalies. [rarediseases.org]

Trisomy 22q

Our patients are 2 of the very few published cases of familial recurrence of 22qter duplication syndrome characterized by array CGH, and they represent unusually mild phenotypes [karger.com]

Novel Insights • Familial reoccurence presented in this paper is extremely rarely reported. • Our patients have unusually mild clinical symptoms - they share very similar [karger.com]

Opitz G/BBB Syndrome Type 2

A structure-function study of MID1 mutations associated with a mild Opitz phenotype. Mol Genet Metab. 2006;87:198–203. [0-www-ncbi-nlm-nih-gov.brum.beds.ac.uk]

phenotypes in a series of patients with Opitz GBBB syndrome with MID1 mutations. 6 61 So J...Schweiger S 15558842 2005 6 Duplication of the MID1 first exon in a patient with [malacards.org]

Mild phenotypes in a series of patients with Opitz GBBB syndrome with MID1 mutations. Am J Med Genet A. 2005;132A:1–7. [0-www-ncbi-nlm-nih-gov.brum.beds.ac.uk]

Autosomal Recessive Mental Retardation Type 2

A novel familial BBS12 mutation associated with a mild phenotype: implications for clinical and molecular diagnostic strategies. [revistabiomedica.org]

Monosomy 4q

Mild Phenotypic Manifestations of Terminal Deletion of the Long Arm of Chromosome 4: Clinical Description of a New Patient. [rarediseases.org]

Mild phenotypic manifestations of terminal deletion of the long arm of chromosome 4: clinical description of a new patient. Clin Genet. 1997;52:116-19. [rarediseases.org]

Chromosome 4q32.1-q32.2 Triplication Syndrome

Four previously reported patients with 4q duplications had HD: two with duplication resulting from t(4;14)(q31.3;p11.2) who had a very mild phenotype similar to our patients [ashg.org]

[…] have imbalances that consistently give rise to relatively mild phenotypic abnormalities. [jmg.bmj.com]

Familial tandem duplication of bands q31.1 to q32.3 on chromosome 4 with mild phenotypic effect. [ngrl.org.uk]

Chromosome 18q Duplication

PMID: 15103719 Interstitial deletion of the long arm of chromosome 18, del(18)(q12.2q21.1): a report of three cases of an autosomal deletion with a mild phenotype. [pubmed.ncbi.nlm.nih.gov]

The dup(18q)/del(18p) recombinant patient with the milder phenotype, the one with the smallest structural aneuploidy, shared partly the mild clinical phenotype in the patients [nature.com]

Duplication 18p with mild influence on the phenotype. [seizure-journal.com]

Glutaric Aciduria Type 1

Mild phenotype of glutaric aciduria type 1 in polish patients - novel data from a group of 13 cases. [medlineplus.gov]

Congenital Disorder of Glycosylation Type 2B

Exceptionally mild phenotypes As mentioned above, patient #11 had a squint since the age of 2 months. [ojrd.biomedcentral.com]

PMID: 19168813 Congenital disorder of glycosylation type 1a: three siblings with a mild neurological phenotype. [pubmed.ncbi.nlm.nih.gov]

Congenital disorder of glycosylation type 1a: three siblings with a mild neurological phenotype. J Clin Neurosci 2007;14:668-72. [atm.amegroups.com]