Familial Mediterranean fever (FMF) is an autosomal recessive disorder, particularly common in the Mediterranean area. Mutations in the MEVF gene cause it. AA Amyloidosis is the most severe complication of FMF leading to chronic renal failure. We describe a rare pediatric case of a phenotype I familial Mediterranean fever with V726A heterozygous mutation. The diagnosis was made at chronic kidney disease. We discuss through this case the importance of the early diagnosis of FMF heterozygous children which is not usually evident in some phenotypes. It will surely avoid fatal complications, inappropriate therapeutic approaches and higher healthcare costs.

UNASSIGNED: Familial hypercholesterolaemia (FH) is an autosomal dominant genetic condition predominantly caused by the low-density lipoprotein receptor (LDLR) gene mutation.
UNASSIGNED: This is the case of a 54-year-old Malay woman with genetically confirmed FH complicated by premature coronary artery disease (PCAD). She was clinically diagnosed in primary care at 52 years old, fulfilling the Simon Broome Criteria (possible FH), Dutch Lipid Clinic Criteria (score of 8: probable FH), and Familial Hypercholesterolaemia Case Ascertainment Tool (relative risk score of 9.51). Subsequently, she was confirmed to have a heterozygous LDLR c.190+4A>T intron 2 pathogenic variant at the age of 53 years. She was known to have hypercholesterolaemia and was treated with statin since the age of 25. However, the lipid-lowering agent was not intensified to achieve the recommended treatment target. The delayed FH diagnosis has caused this patient to have PCAD and percutaneous coronary intervention (PCI) at the age of 29 years and a second PCI at the age of 49 years. She also has a very strong family history of hypercholesterolaemia and PCAD, where seven out of eight of her siblings were affected. Despite this, FH was not diagnosed early, and cascade screening of family members was not conducted, resulting in a missed opportunity to prevent PCAD.
UNASSIGNED: Familial hypercholesterolaemia can be clinically diagnosed in primary care to identify those who may require genetic testing. Multidisciplinary care focuses on improving identification, cascade screening, and management of FH, which is vital to improving prognosis and ultimately preventing PCAD.

Carbamoyl-phosphate synthetase 1 (CPS1) deficiency is an autosomal recessive congenital urea cycle disorder (UCD) characterized by hyperammonemia. The recipients of liver transplantation (LT) for UCD are often children, and the potential donors are often the parents. Hereditary congenital diseases involving UCD entail the possibility of both parents being genetically heterozygous. Herein, we describe the case of a 12-year-old girl with CPS1 deficiency receiving a liver transplant (soon after birth) from her father, who had a heterozygous CPS1 mutation. She was referred to our hospital with respiratory distress after contracting two infections (respiratory syncytial virus and human metapneumovirus) within a short period, both of which presented with hyperammonemia. Medication for hyperammonemia quickly lowered the ammonia levels. The hyperammonemia was thought to be caused by the heterozygous mutation in the donor liver; moreover, it is likely that the low enzyme activity in the patient\'s liver was increased due to the infections. This is the first study to report hyperammonemia in a CPS1 deficiency patient due to an infection after LT. Thus, patients with CPS1 deficiency should be aware of the development of hyperammonemia after LT.

POLR3B encodes the RPC2 subunit of RNA polymerase III. Pathogenic variants are associated with biallelic hypomyelinating leukodystrophy belonging to the POLR-related disorders. Recently, the association with dominant demyelinating neuropathy, classified as Charcot-Marie-Tooth syndrome type 1I (CMT1I), has been reported as well. Here we report on an additional patient presenting with developmental delay and generalized epilepsy, followed by the onset of mild pyramidal and cerebellar signs, vertical gaze palsy and subclinical demyelinating polyneuropathy. A new heterozygous de novo missense variant, c.1297C > G, p.Arg433Gly, in POLR3B was disclosed via trio-exome sequencing. In silico analysis confirms the hypothesis on the variant pathogenicity. Our research broadens both the genotypic and phenotypic spectrum of the autosomal-dominant POLR3B-related condition.

UNASSIGNED: In hemoglobinopathies, a basic lesion alters the rate of globin synthesis or the structure of the globin in healthy hemoglobin (Hb). Genetic instructions are used to synthesize the polypeptide chains that make up globin chains. The kind and extent of the structural aberration of the Hb molecule are closely related to the clinical features. Hematologically, the heterozygous form of the Lepore syndrome has a pattern resembling minor thalassemia, and electrophoretically, it is characterized by aberrant Hb Lepore fractions at a rate of 5-15% and a decreased percentage of HbA and mildly increased HbF. Clinically speaking, Hb Lepore heterozygotes patients are asymptomatic and resemble the clinical picture of patients with mild thalassemia.
UNASSIGNED: A 28-year-old female came to our attention for assessment of generalized weakness and fatigue for a 4-month duration. Laboratory evaluation, including complete blood count, showed mild microcytic hypochromic anemia with parameters resembling the thalassemia trait. Iron profile studies were normal. Abdominal ultrasound showed mild splenomegaly. Hb electrophoresis was performed and showed an abnormal high-performance liquid chromatography pattern with an abnormal Hb band, mild elevated HbF, and mild reduction in HbA. The interpretation of the Hb electrophoresis curve suggested heterozygosity for beta chain variant Hb Lepore.
UNASSIGNED: Hb Lepore is one of the structural Hb variants with a characteristic fusion gene between the delta and beta chains. Hematologically, the heterozygous form of the Lepore syndrome has a pattern resembling the thalassemia trait. In Palestine, the prevalence of Hb Lepore, either homozygous or homozygous state, is unknown.

Background: Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) is an autosomal recessive disorder characterized by baldness, recurrent ischemic stroke, lumbago, headache, and dementia which is closely related to homozygous mutations of the high-temperature requirement serine peptidase A1 (HTRA1) gene. Heterozygous mutations of HTRA1 are usually considered to be non-pathogenic. Although it has been revealed that only a few patients with heterozygous mutations could present some manifestations, their clinical symptoms were atypical, milder, and always with a lower frequency of extra-neurological features. Here, a rare patient with heterozygous mutation of HTRA1 who had all typical features of CARASIL as well as severe clinical symptoms and rapid progression was initially reported in our study. Case presentation: A 43-year-old female patient presented with a gradual onset of headache and cognitive decline. As time progressed, her headache intensified and symptoms of dementia began to manifest gradually. During her early years, she had thinning hair and subsequently experienced two occurrences of ischemic strokes in her thirties. Furthermore, she also had a history of lumbago and urinary retention before visiting our hospital. The patient\'s magnetic resonance imaging revealed the presence of widespread white matter lesions, infarctions, and microbleeds, in addition to lumbar disc herniation and degenerative lesions. The observed clinical characteristics had a strong correlation with CARASIL, and the patient was diagnosed with a heterozygous missense mutation of 905G>A (Arg302Gln) in the HTRA1 gene. The patient has been under continuous follow-up for a duration exceeding 3 years subsequent to her release from the hospital. She underwent cystostomy, and symptoms of bulbar paralysis developed in a progressive way. Currently, there has been a notable decrease in motor function and activities of daily living, resulting in the individual being confined to bed for a duration exceeding 1 year. Conclusion: This case suggests that patients carrying a heterozygous mutation in G905A may also have typical clinical features of CARASIL, which allows us to have a more comprehensive understanding of CARASIL.

Achondroplasia is a congenital skeletal system malformation caused by missense variant of FGFR3 gene with an incidence of 1 per 20,000-30,000 newborns, which is an autosomal dominant inheritance disease. Despite similar imaging features, the homozygous achondroplasia is absolutely lethal due to thoracic stenosis, whereas heterozygous achondroplasia does not lead to fetal death.
A fetus with progressive rhizomelic short limbs and overt narrow chest was detected by prenatal ultrasound in the second trimester. Gene sequencing results of amniotic fluid sample indicated a rare missense variant NM_000142.4: c.1123G > T(p.Gly375Cys), leading to a glycine to cysteine substitution. Re-sequencing confirmed that it was a heterozygous variant, and thoracic stenosis was then confirmed in the corpse by radiological examination.
We identified a heterozygous variant of the FGFR3 gene as the rare pathogenic variant of severe achondroplasia in a fetus. Heterozygous variants of p.Gly375Cys may have a severe phenotype similar to homozygote. It\'s crucial to combine prenatal ultrasound with genetic examination to differentiate heterozygous from homozygous achondroplasia. The p.Gly375Cys variant of FGFR3 gene may serve as a vital target for the diagnosis of severe achondroplasia.

Dyskeratosis congenita (DKC), also known as Zinsser-Cole-Engman syndrome, is a telomeropathy typically presenting as a triad of leukoplakia, nail dystrophy, and reticular hyperpigmentation. Reported genetic mutations linked to DKC include DKC1, TINF2, TERC, TERT, C16orf57, NOLA2, NOLA3, WRAP53/TCAB1, and RTEL1. Homozygous, compound heterozygous, and heterozygous mutations in RTEL1 (RTEL1, regulator of telomere elongation helicase 1) gene on chromosome 20q13 are known to cause autosomal dominant as well as recessive DKC. Pathogenic variants of RTEL1 gene in DKC patients include c.2288G>T (p. Gly763Val), c.3791G>A (p. Arg1264His), and RTEL p. Arg981Trp. We report a novel homozygous variant of RTEL1, transcript ID: ENST00000360203.11, exon 24, c.2060C>T (p.Ala687Val), in a patient of DKC presenting with leukoplakia, dystrophic nails, reticulate pigmentation, and positive family history of a similar phenotype. The novel variant, reported as a variant of uncertain significance, may therefore be considered diagnostic for DKC in a Pakistani population.

Pathogenic germline variants in the CHEK2 gene have been shown to cause a moderate increased risk of breast cancer. Here, we present a striking CHEK2 family with a biallelic carrier of two frameshift pathogenic variants, to draw attention and to encourage a comprehensive genetic and cancer risk education for biallelic carriers of CHEK2 pathogenic variants.

Homozygous mutations to NTHL1 are known to increase cancer risk, particularly in the colon and breast. NTHL1 tumor syndrome (NTS) is an autosomal recessive genetic condition. Little is known about the cancer risk in patients who have heterozygous NTHL1 mutations. We previously published a case of benign tumors associated with a heterozygous NTHL1 mutation. In this second case, we present a patient with a heterozygous NTHL1 mutation who developed a gastrointestinal stromal tumor, pilocytic astrocytoma, tall cell papillary thyroid cancer, invasive ductal papilloma, spinal nerve sheath tumors, and spinal hemangiomas. Here, we show that heterozygous NTHL1 mutations may increase cancer risk and may even manifest similarly to NTS.